Yes, the idea of selling t-shirts as a fund-raiser for this site is a brilliant idea! I think that would be something that would not only benefit this site and allow the generous people who run it the ability to do the things that they deem necessary to improving it, but could also help raise awareness of the community and provide its members with some fun and good-looking apparel to wear.
i have always liked the eu name prefix. Instead of Mr. i always use eu in front of my name. If someone asks, i let them know that i am not a "complete male", and that i was castrated. As i am not Transgender, the eu just seems to fit better. i also like the "scrotum for rent", as it just seems more polite than putting something like CASTRATED or NO BALLS. Anyone who reads it would know that the person wearing the shirt has an empty scrotum. If i saw a shirt with CASTRATED on it and then one with SCROTUM FOR RENT, i would be more inclined to believe the person wearing the SCROTUM FOR RENT is a eunuch. CASTRATED might lead people to believe he is a heavy rock fan, or into goth, etc. but not really believing he is a eunuch.
As a prefix, eu is perfect. On a T-Shirt is really discreet, but might be too discreet. One might just pass by not noticing. On a T Shirt SCROTUM FOR RENT says it all. That's my favorite. Just my 2 cents.