I like chun-li's Kikosho. Aside from sounding like 'kickass', it deals a 20 hit combo against cornered opponents and you can juggle it as long as you have the energy.
[img]http://vignette3.wikia.nocookie.net/streetfighter/images/e/e4/Kikoshou.gif/revision/latest?cb=20100701041630[/img]

I've always liked tatsumaki but my favorite use is Kens Shippu Jinraikyaku
[img]http://vignette2.wikia.nocookie.net/streetfighter/images/e/ea/ShippuJinraikyaku.gif/revision/latest?cb=20101122215316[/img]