Hard Drive: Western Digital Caviar 250 GB
The drive in this build is a pretty standard 250 GB SATA drive. Hard drive performance will suffer compared to the high-end builds, but it shouldn't impact the total performance all that much. We should note that we used this drive because it was on-hand and it fits the purpose of a budget drive. If we were to purchase a new part today, we would have likely opted for the Western Digital Caviar 320 GB drive, which can be purchased for $80 online but has an extra 70 GB of space.
Case: Raidmax Smilodon
The Smilodon is a relatively low-cost case with subjective styling but - more importantly - lots of case fans, and it's not terribly loud. Airflow at a decent noise level is a very important feature for any overclocker, and the Smilodon does it on a budget.
Power: Aerocool Zerodba 620w
Stable Power is a staple of a good overclocking system - never underestimate the importance of a solid PSU in any system if stability is important to you. With only a single graphics card to worry about, the 620W Zerdoba should have no trouble powering to the P5B, CPU and 8800 GTX.
Optical Drive: Sony Optiarc 7170
This is the standard drive we've used in all of our marathon builds thus far. Nothing much to say about it except it's nice to have a SATA DVD-ROM, so we don't have to use those terrible IDE cables.