You'll find two favorites for fans:
Panaflo (Panasonic) L1A (Will soon be getting these, but have not yet used any)
Enermax temperature controlled fan (great little fan, and unlike the Panasonic ones, has a normal fan connector)
Both are quiet and should have a long life.
For a hard drive, you really don't need too much air moving--you just need
some air moving. With an ideal case environment, the air being sucked in around the HD from the top-rear exhaust fan would be enough...but not everyone has such an ideal situation.
For the GF4: Zalman's heatpipe cooler, Vantec's Iceberg (requires epoxy), or Zalman's northbridge cooler (requires ghetto-rigging or epoxy). I use the Zalman northbridge cooler, but on most new video cards, it takes some work to mount it w/o adhesive, and you *might* still need a fan (but probably not). When I got mine, I didn't get the Vantec because I wanted it to be removable easily, but the Zalman NB32j was a PITA to install for the first time. Installing it on motherbaords like it was meant to be is far easier
