Love At First Sight/Web Comics

The Law of Purple: Red falls for Rose on first sight. Much of the attraction is that she's thrashing a purse-snatcher at the time, as seen here.
In Girl Genius, Zola plans to manage her meeting with the heir to the Storm King—and make it look like Love At First Sight.
- Zeetha's first meeting with Higgs is like this. For her. For him, its one of the few things that terrifies him.
Minus: what happens when Cupid gets really out of hand.
Xkcd: This comic
Homestuck: Trolls, due to Bizarre Alien Reproduction, have a form of romance which is essentially hateful archnemesishood. The first time Karkat sees John, he is instantly struck by total, all-consuming, overwhelming hate, complete with spade-shaped Wingding Eyes.
- And then there's Vriska and... Nicolas Cage.
Subverted in Dresden Codak. Kimiko sees a handsome guy with an FM-2030 book and instantly turns into a tongue-tied twit, fantasising about either an idyllic relationship (on an airship!) or a UST-laden scholarly rivalry. See here. Unfortunately for her, he turns out to be kind of a moron.
In Endstone, Jon disowns believing in this when he first met Kyri.
Ls Empire has an entire species (Kayoss) that falls in love this way, mainly due to their Magic Genetics. This does have a side effect (referred to as Love Struck) which involves light headedness, drooling from the eyes, and passing out.