As one of its daily deals, HoboNinja offers this Star Trek #1 Fan T-Shirt for $9.99 with free shipping. That's $21 under the lowest total price for a similar Star Trek T-shirt elsewhere, although we saw it for buck less last year. It's available in sizes S to XL. Deal ends April 19.
Note that size XXL is available for an extra 99 cents, and size 3XL for an additional $1.99.