I wish I could buy into stocks, derivatives, bonds and all that through Bitcoin, have it settled via fiat and have my profit returned in Bitcoins. That would be incredibly cool.
I was looking to buy stocks with bitcoin few days back and posted a thread in india forum since I primarily wanted to buy Indian stocks
https://bitcointalk.org/index.php?topic=1396214.0 and a member mentioned Getkeza.com that offer investing in stocks with bitcoin.You can try it