T-shirt expansion. You could also make it sleeveless and only sew on sides for the lower portion (with lace or other fabric, too), leaving a gap for the arm holes. But not see thru lace, thats trashy.
I like bows
Back Cut Out T-shirt – DIY
DIY Book Clutch Tutorial from Caught on a Whim. For more book clutch DIYs including a roundup go here: truebluemeandyou.tumblr.com/tagged/diy-book-clutch
alice in wonderland and cheshire cat - book art
OH SO PRETTY the DIARIES: 299 no-sew ways to alter a t-shirt
Corset making secrets. I don't really need this, but I might later.
Dragon scales made out of duct tape. The instructions are for a bottle cover, but could be very useful for cosplay!
Cute galaxy DIY shirt
Grommet Shoulder Top | 31 T-Shirt DIYs That Are Perfect For Summer http://www.trashtocouture.com/2012/02/my-laced-up-collar-sleeves-diy.html
DIY Geometric Wall Decals - This DIY Geometric Wall Art Livens Up Any Room Without Permanent Change (GALLERY)
Fun DIY Craft Ideas - 72 Pics Wouldn't this be great with a big canvas....and put a light bar behind it?
DIY Clothing Tutorials / T-shirt ideas:
Transform a too tight shirt into a fashion statement with a lace panel insert.