http://www.splitreason.com/  
 
Not sure how well known this place is, but I heard about it on a episode of Talkradar and I gotta say, these are some of the best gaming related shirts ive ever seen. heres some examples of the shirt designs:   
      
    
    
    
    
 
and heres some great nongame related stuff they have  
 
   (I think this is my Fav. one)  
    
 
Seriously, I can spend like a crap ton of money here. Where do you get your gaming apparel at?