Powerful Pick

"A powerful attack which drains 5% from your opponent's Attack, Ranged and Magic. This attack takes longer to perform than a normal attack."

—--RuneScape, Dragon Pickaxe Special Attack

A Sub-Trope of Improvised Weapon and closely related to Shovel Strike, pickaxes are commonly used to break up rocks and earth but also can immediately be used as a weapon. While usually not as sharp as a conventional melee weapon, the narrow spike and heavy head of the pick make it effective against armor. Because of their original purpose, they're also exceptionally sturdy and not as likely to break as other improvised weapons. Ice picks, used as a climbing aid in icy regions, are also covered by this trope. Though smaller than mining picks, their blades will tend to have a sharper edge and the weapon will be easier to both control and conceal.

In real life and fiction, some warhammers and traditional axes also have a big spike on one side of their heads for punching through armor (and, on occasion, ribcages, heads and other things).

Examples of Powerful Pick include:

Film

Both the original My Bloody Valentine and the remake had killers with a pickaxe as their Weapon of Choice.
In Friday the 13 th Part II, Jason's very first kill is the Final Girl of the original, who he kills with an ice pick to the head. Later, he hunts Ginny down with a pickaxe.
Shit gets worse in The Descent when Juno accidentally puts a climbing pick through her buddy's neck after a protracted fight with monsters. After said friend is found by another of Juno's friends (who are now rivals because Juno slept with her husband) she gets hunted down in revenge.
The demon-possessed killer of Happy Hell Night uses a pickaxe.
The killer in Death on Demand uses an ice axe.
Curse of the Forty-Niner, aka Miner's Massacre.
Alissa eliminates most of the remaining characters with a pickaxe she picks up in Blood Night: The Legend of Mary Hatchet.
The villain of Simon Says has a severe pickaxe fetish, to the point of actually constructing a machine gun-like contraption that fires them.

Literature

Kate Connor got a bunch of ice picks on sale because they make good weapons and having them around the house wouldn't be looked at askance.
Discworld's dwarfs use special axes: one side is a pickaxe, in case you need to mine; the other is a traditional axe, in case somebody tries to stop you.

Live Action TV

In an episode of CSI: NY, someone was killed with an ice pick to the neck. As it turns out he was dying of cancer and he requested that he be killed this way.
There was an episode of Bones where a woman was murdered with a pick used for rock-climbing in caverns.
The Criminal Minds: Suspect Behavior episode See No Evil depicted a woman getting an ice pick rammed into her ear.

Tabletop Games

In Dungeons & Dragons, picks are popular weapons among those of the dwarven persuasion, an outgrowth of their traditional profession of mining. They are known for low damage but very powerful Critical Hits (comparable to a scythe). Ironically, picks' low damage means they're unable to damage stone without extraordinary strength, making them useless to use as actual picks. One would assume that they ignore the hardness of stone, like axes do with wood, but it's never specifically stated.
In GURPS, picks are very powerful because they have high basic damage and a high damage multiplier. Their major limitation is that they can get stuck in a target, but even then they automatically do damage when you pull them out.
In the official board game of The Walking Dead, picks are very powerful if you use nothing but picks in a single combat.

Toys

Bionicle: Nuju's Ice Pick and Avak's Seismic Pickaxe.

Video Games

Dwarf Fortress: picks deal piercing damage, which is one of the best ways to damage internal organs (and thus, potentially kill a victim in a single blow depending on where you hit.) The skill that governs weapon use also governs one's skill at mining, and so your best weapon-wielding dwarfs often start off as pickaxe-wielding miners, and may never trade up the pick for a hammer or sword in their life. Try temporarily recruiting a legendary miner (so s/he doesn't run away from the enemy) and not assigning him/her a weapon (so they continue to use the pick.) Ass will be kicked.
Warcraft 3 has the Rusty Pick item, which adds a little damage and has a chance to stun an enemy. Peasants and Peons use them as tools and weapons, if you order them to attack.
RuneScape: partially averted; pickaxes can be wielded as a weapon, but they are less effective than weapons made of the same metal. That being said, players frequently wield their pickaxes while mining, rather than simply wield another weapon, because it saves an inventory space that could be used to carry more ore. Also, some bosses have armor than needs to be broken with a pickaxe before you can actually start hacking away at it's HP with another weapon (though you can still use the pickaxe if you wish).
The Soldier class in Team Fortress 2 has a pick as his unlockable melee weapon called The Equalizer. It turns him into the ultimate Glass Cannon by raising in damage output and running speed based on how low his health level is. At 1 Hit Point, he can hit with 113 points of damage and is almost as fast as the Scout.
Modern Warfare 2: one level has you using ice picks as melee weapons.
- Well, you get to see MacTavish using ice picks as weapons. To dismount a guy on a snowmobile, no less. It's beyond awesome.
An ordinary icepick is the closest thing Ferazel's Wand has to an Infinity+1 Sword, doing many times the damage of a dagger or a fireball spell.
The Imperial Pick from Phantasy Star Online is a very good Partisan weapon, despite being, essentially, a very large and ornate pickaxe.
A pickaxe is also the best weapon in Penumbra: Overture—or more accurately, every other weapon is worse. You'll still have to hit Hellhounds a dozen times to kill them, but two hits can handle a Giant Spider.
Grayback from Battle Realms wields one; justified as he and most of the Wolf Clan pre-revolt were miners.
One of the first weapons in Drakensang 2: The River of Time is a pick, classified as a "Two-Handed Axe" type weapon.
The Pickaxe of Despair is by far the most damaging-per-swing weapon you can find in Silent Hill 4: The Room, and its Charge Attack is a 720 degree Spin Attack that will kick anything close to you away by a good 7 feet. The drawback is that the thing is so slow that you'll often get hurt while trying to use it, taking around 4 seconds for a single attack and over 20 to charge a spin.
Morrowind has mining picks that can be equipped as weapons, but they're pretty useless in combat.
Skyrim includes picks, which are required to mine ore. They can make a decent weapon if enchanted.
Some enemies in Red Dead Revolver wield mining picks in melee combat.
You can use your pick this way in Minecraft, but usually it's better to stick to swords or bows, as using your pick as a weapon deals less damage than either of those weapons and you cannot block with it like you can a sword.

Real Life

Leon Trotsky was assassinated with either an ice axe or an ice pick, depending on who you ask.
The horseman's pick and other warhammers often had large pick-ends for piercing armor.
Karla Faye Tucker was executed in 1998 for killing someone with a pickaxe.