It's been over a month... hurrah!

Has anyone seriously studying Japanese actually learned something useful from this site?

Update: Due to the overwhelming response, I'm going on hiatus.

発音 - pronunciation (n) - hatsuon

Jamaican borrowed from Speak Jamaican.

服 - clothes (n) - fuku

辛い - spicy (adj) - karai

大勢 - a great number of people (n) - oozei

早退します - leave eary (verb III) - soutaishimasu

一生懸命 - with all one's effort (adv) - isshoukenmei

情報 - information (n) - jōhō

歌手 - singer (n) - kashu

弱い - weak (adj) - yowai

お祝い - celebration (n) - oiwai

乾く - dry (verb I) - kawaku

外します - be away (verb I) - hazushimasu

Dan's Lunch
Terry Tate

呼びます - call (verb I) - yobimasu

必ず - without fail (adv) - kanarazu

青い - blue (adj) - aoi

発明します - invent (verb III) - hatsumeishimasu

渡る - wataru (verb I) - cross

知識 - chishiki (n) - knowledge

優勝します - yuushoushimasu (verb III) - win the championship

重い - omoi (adj) - heavy

測る - hakaru (verb I) - measure

空気 - kuuki (n) - air

泣く - naku (verb I) - cry

遊びます - asobimasu (verb I) - play, enjoy oneself

減ります - herimasu (verb I) - decrease

I believe I may have misunderstood the context of this verb, as my trusty Langenscheidt tells me that heru translates to "decline, drop off, shrink" (lending itself to further and perhaps more graphic representations). Oh wells.

参加 します - sankashimasu (verb III) - attend

歴史 - rekishi (n) - history

相談します - soudanshimasu (verb III) - consult

うわさ - uwasa (n) - gossip

働きます - hatarakimasu (verb I) - work

守ります - mamorimasu (verb I) - obey

特別 - tokubetsu (na adj) - special