The problem : Drupal awfully slow on Vista (and Seven) with Wampserver
For some time now, I'd been severiously annoyed by the (utter lack of) performance of Drupal 6 and 7 on my home PC, which happens to be running Microsoft Vista: considering I was used to getting page times around 200ms on a fractional Celeron with Apache 2.2 on a Linux server hosted comparatively far across the net from that same machine, I felt the 5 to 15 seconds response time per page on this local machine with a quad core and 3 GB RAM were really making me lose my time.
After some time spend googling around, I stumbled upon an incredibly simple tip, which made the 5 to 15 seconds per page drop down to around 1 second when logged in, and well below 500 ms when not logged in. It's incredible what ONE single character in a plain text file gets you under Vista :-)
UPDATE 2010-01-23: David Hogg tells us (see below) that this works for Windows Seven too