Found this idea from Generation T. It's actually my very first DIY/Recon project and I'd have to say that the simplicity of it just took my interets and I thought I'd give it a try. Cool idea.
T-Shirt to Halter Tutorial
Large Baseball T Converted into Cute Halter
A chic, sweetheart-cut halter top w/ bow detail on back
You don't want your bra straps to show under your halter, and you defently don't want to go without a bra!
Already posted but noooow its a how-to
easy but particular!