1: doubleclick character and press ⌘ c
2: go to Twitter.com and press ⌘ v

☉	☇	☈	☡	✠
☊	☋	☌	☍	♁
✇	☢	☣	✣	✡
☞	☜	✜	✛	❥
♈	♉	♊	♋	♌
♍	♎	♏	♐	♑
♒	♓	☬	☫	☨
☧	☦	✁	✃	✄
✎	✐	❂	❉	❆
♅	♇	♆	♙	♟
♔	♕	♖	♗	♘
♚	♛	♜	♝	♞

We ✍ these ☭ too:
TwitterCounter & TwitterMail