moblog.co.uk is holding a t-shirt competition. it does not say till when, but designs can be submitted by sending them to tshirtcomp@moblg.net.
You can submit anything you want for your design, as long as it fits into 297mm W by 420mm H. Images for print should be as 297mm W by 420mm H size, 300dpi, tagged TIFFs, but as they’re huge files, please submit a screen sized jpg as your entry. There’s more information available here: http://moblog.co.uk/cblog.php?show=2242
Winners will have their designs printed, and will receive a free t-shirt of all the designs printed.