It does not seem like it was all that long ago that 2GB was more than plenty of memory for a well-heeled system. These days 8GB is more the norm and 16GB, like the two kits from Crucial and GeIL in today's roundup, are certainly common. We also have a water cooling kit from EK for you to check out.
EK H30 360 HFX Watercooling Kit @ ThinkComputers
Crucial Ballistix Tactical Tracer DDR3-1866 16GB Quad Channel Memory Kit @ ThinkComputers
GeIL EVO VELOCE 16GB Dual Channel 2133MHz C10 Memory Kit @ Madshrimps