what's this thing?

To owe your Tweeps a beer, @-reply to tweetbeer like this: 
@tweetbeer @mattallen for the memories
Tweetbeer will let your Tweep know about their cold one and record the debt here for later collection and posterity.
bmatt owed a beer to lachie for introducing me to Merb (and to tweetbeer) ;-). about 2 days ago
hassox owed a beer to mattallen for this awesome service. about about 1 month ago
emacsian owed a beer to codeshepherd for just like that!. about about 1 month ago
philmorle owed a beer to mcannonbrookes for being cool. about about 1 month ago
rosshill owed a beer to sandraarico for because we missed out on coffee this morning!. about about 1 month ago
gevason owed a beer to lachie for cool tweetbeer app. about about 1 month ago
lachie owed a beer to lachlanhardy for Webjam. about about 1 month ago
Tom_Voirol owed a beer to mcannonbrookes for not hiring me. But he just brought me one so that's OK. about about 1 month ago
lachie owed a beer to mattallen for buying me a beer. about about 1 month ago
mattallen owed a beer to lachie for regex wizardy. about about 1 month ago
aussiegeek owed a beer to nigel_rausch for time machine on ubuntu instructions. about 2 months ago
gnoll110 owed a beer to mattallen for the lift to the RoRO Sydney meetup!. about 3 months ago
schlick owed a beer to mattallen for the lift to the Sydney Ruby meeting. about 3 months ago
mattallen owed a beer to lachie for showing him the create_or_initialze_by_XX method in tweetbeer.com. about 3 months ago
whalec owed a beer to mattallen for Tweetbeer!. about 3 months ago
lindsayevans owed a beer to mattallen for tweetbeer.com. about 3 months ago
snapperwolf owed a beer to mattallen for schooling in tweetbeer fun!. about 3 months ago
kouky owed a beer to mattallen for the MYOB of beer. about 3 months ago
Broady owed a beer to mattallen for the memories. does this actually work? it didn't last night.. about 3 months ago
hughevans owed a beer to sclick for putting on CRC at his joint.. about 3 months ago
nateritter owed a beer to mattallen for launching tweetbeer.com. about 3 months ago
nateritter owed a beer to mokolabs for introducing me to @tweetbeer. about 3 months ago
mokolabs owed a beer to lachie for launching tweetbeer.com!. about 3 months ago
mokolabs owed a beer to mattallen for launching tweetbeer.com!. about 3 months ago
lachie owed a beer to benaskins for GenLevel. about 3 months ago