I need a physically flat or small subwoofer....

I am not a big home-theater guy, so I don't intend to put alot of effort into this; however, I have a two-way setup for watching movies and I thought I would add a subwoofer for just a little bit of oomph. My problem is that I don't have alot of room and I need a self powered subwoofer with a low profile. I saw one, once, made by Magellan, but that subwoofer is way more than I want to spend. I have also seen some made by Advent, but they are for PC setups. Anyone know of anything else that might work for me. I don't need alot of power as it will probably be in a corner in one of my small rooms. TIA