Back in 99' when 99% of the world still used IE as an internet browser, not allowing png's in hotlinks or signatures makes sense. But i think enough people use browsers that actually display png's correctly that they should be implemented. Heck, the big white squares some will see might be incentive enough for them to move on to greener pastures. Being a "graphics guy", png's are the wonder bread of image formats. With alpha blending, almost no loss in quality and transparency, they are wonderful. Allowing the use of these would make things so much better not only for myself, but for i'm sure a considerable amount of others on this board that would like to use png's.