Since we like to post brain games on here.
A whole list of mainly browser games: http://nl.reddit.com/r/leagueoflegends/comments/15tz93/here_are_a_few_reflexereaction_games_to_improve/ (look at me reposting)
I really like invisblecursor, my highscore on there is 308 so far
LOL thank you Bramski, this reddit post is a goldmine <3 Nice score on InvisiCursor! My favorite so far is the Multitask 2 Challenge mode, such a fun concept aha
Yea i've been doing some multitask aswell. Maybe I suck at it but I never feel like trying multiple times.
I recommend downloading gridwars aswell, lots of fun although the controls are not super smooth IMO.