The SMC that I have with the newest firmware supports packet filtering..I got it for 50, although after a 50 dollar rebate. It's an awesome router, I use it, and would recommend it highly...like I said the new firmware adds packet filtering support also! (I have the SMC 7004BR I believe)
Update: Oh yeah, I forgot that the SMC also has a print server and a built on com port for you can hook up an external modem for it to connect in case the broadband goes down. The only thing I don;t like..is the no logging of everything that happens (only shows you like the last 30-40) as far as access wise, and also no telnet/ssh access.