I got a Deka ETX20L battery. Small and powerful too. I got it through an electrician my dad knows, only paid $180 bucks.
Dimensions:(L x W x H) 114.3mm x 99.06mm x 215.9mm
CCA: 270
Might be something to consider..not really ideal if you have a huge soundsystem or something though.
its a jetski/atv/motorbike battery but I had no trouble with them. I had it out of the car for a good 3-4 months, and also jump started from it a couple of times..and when i put my car back together, and hooked it up..started straight away to my amazement..