Good thread.
First and foremost, they are all free.
FakeClockUp - the pioneer, straight forward, 1x, 1.4x, 1.6x, etc. EDIT: 0.2-1 (the latest) on some unofficial repos requires respring every time to take effect. Get it from Novi's repo to have the same version number but the correct one that doesn't require respring. hitoriblog.com/apt is the repo
Accelerate - on BigBoss repo. clever names, like 'Ferrari' and 'Impusle Drive' (still no update to address that typo, really?), but has no icon in Settings and you can't tell in terms of actual speed improvement what corresponds with what exact multiplier like FakeClockUp.LUCKILY, advantage is you can disable speed up animations in certain situations like for icon wiggle when moving them (not perfect though, the icon you select to wiggle still wiggles quickly in a lot of speeds and animated gifs are still going at warp speed and animations in certain apps like Turntable, heads bob at a milion miles an hour)
%hookslaw- speeds up going between windows in a screen, opening and closing animations, but not everything (and nothing else really-- so animated gifs aren't cracked out nor icon wiggle, etc). Doesnt require respring either, the only downside is it requires a bit of trial and error to get a good setting going; there are a handful of variables to modify. The trickiest in that regard, but arguably the most rewarding. I've come to like the bouncy effect it has too.
I went in that order using them. FakeClockUp->Accelerate->%hookslaw (2nd time, its staying I believe)
FakeClockUp I think was first offered on a chinese repo known by few and blew up over time, Accelerate like a 13 year old or something (which is incredible, I wish I could write accelerate period), and %hookslaw is made by Chpwn your favorite Zephyr dev, Infini-dev, Gridlock, Facebook employee, generally awesome developer.
I just got Webscrollian too by him, NO MORE scrolling endlessly for long safari pages. So nice.