[karthikksv]

Oh, no I haven't. Looks like they beat me to it in terms of features and sharing.

It seems like they could make it easier to use, though. You have to go to their custom styles page and add CSS without seeing its effects directly. Their userstyles.org website also needs some help (perhaps someone should make a stylish style for userstyles.org itself). Nevertheless, the sharing features are quite nice. I wanted to add such sharing capability myself.

[alphakappa]

Your project is still pretty good. Thanks for sharing (especially, for putting it up on github, so others can use some of this if necessary)

[SippinLean]

>without seeing its effects directly

Nope, Stylebot has live CSS editing, it shows you the results as you type.