Animation Age Ghetto: Briefly averted, as TCM managed to air some classic cartoons for a short time, including a beautifully restored version of Mr. Bug Goes to Town. Unfortunately, this was very short-lived.
Another aversion came with a retrospective of the work of Hayao Miyazaki and Studio Ghibli in January 2006, running both the English-dubbed and subtitled versions of their films (with the exception of Only Yesterday, which was shown only in its subtitled version).
Another near-aversion would be when they almost aired Popeye Meets Ali Baba recently, but a schedule mix-up ended up keeping it off-air by accident.
Network Decay: A stunning aversion. Seriously, go look at the Network Decay page, there's a whole section devoted to how heroically they avert this trope.
Notably, there are very few post-2000 films shown; the most recent movies featured on the channel seem to be Spirited Away (2001) and The Lord of the Rings: Return of the King (2003), both of which aired as part of their "31 Days of Oscar" theme month.
Even more impressive? In a World where every basic cable channel seems to be about "maximizing profit" and squeezing commercials into every nook and cranny (so that you won't change channels, don't you know), TCM steadfastly refuses outside advertising [1] and runs everything uncut (even if it's rated R or TV-MA). And the network has been this way from the very beginning. This near-insane dedication to task won them a 2008 Peabody Award.
Rescued from the Scrappy Heap: Did this for Ted Turner, who was previously reviled by cinephiles for his enthusiastic support for colorizing old black & white films.
↑(the closest they have to commercials are spots for their website, where they sell DVDs and whatnot, and their printed programming guide...and these are only shown between films, never during)