(and I want the Shakespeare tee ... will it be available on menswear?)
The t-shirt is actually already available, it's part of a collection of t-shirts she has designed for Comic Relief (a big annual charity event here in the UK). They are available at TK Maxx now in unisex sizes and are only £9.99 each!
http://www.tkmaxx.com/get-your-red-nose-day-t-shirt-here/page/tshirts/