Heted bed not integrated into Ramps?

Hey everyone,

I am wondering if anyone uses a heated bed for ABS (up to around say 110 degrees) for their printer?

I ask because I am just having so many problems trying to heat a bigger bed with 12V, and it's all because of the heated bed.

I am wondering if there is anything I can buy/build that would let me say plug into a 110V outlet that will allow me to control the temperature like Ramps does.

I would like to be able to heat a bed up that is anywhere from say 300mm x 300mm up to even say 500mm x 500mm


Thanks.