In no particular order:
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Get back the high score on Slither.
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Improve the high score on Snake Pit
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Get back the high score on centtime
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Beat negative1's scores on Centipede and Joust 2 so that I can ask to have them removed without appearing to have an ulterior motive.
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Put in the effort to have a serious go at the higher scores on Joust.
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Become expert at Defender.
I assumed you meant goals about playing games, and so didn't list stuff like banning all Mah Jong games, archiving Pac-Man as soon as a couple more people submit perfect scores on it, etc...