I have spoken of 1broker before with a litte review, full text here
Lately the website changed UI but that doesnt matter..
They have added cooler thing - you can choose traders and just copy their moves with any amounts you wish!
1Broker Description
Its an old forex/CFD site where using BTC you can anonymously trade stocks, currency pairs and commodities. The fees on site are pretty low. and more explained below.
If you just want to use the site for buying stocks of some companies with BTC.. Theres plenty.
Copy Other Traders
The minimal trade is 0.001 BTC so its suggested to put 0.1-0.05 at least to test it.