Mishimoto intercoolers offer great cooling for a decent price. Mishimoto intercoolers are available in different sizes and come in silver, black or gold finishing.
The intercooler cools down air from the turbo, packing it more compactly, reducing heat and thus giving more power. The intercooler is one of the easiest and cheapest ways to gain horsepowers.
Mishimoto is a popular brand, also offering the coolers in a black finish which helps to radiate some heat away.