Radio Shack online (Note: Online deal only) has this Sandisk 8GB Cruzer for a total of $19.99 shipped. Although the description lists compatibility with Windows/Vista - that’s only for the Ready Boost crapware that installed on the disk. You can use this in any machine you please.

Supercharge your PC’s performance with SanDisk USB flash. This 8GB Cruzer is enhanced for ReadyBoost. When you plug in the drive a simple menu entry will allow you to use the drive for storage or to boost your system performance. Its also U3 smart enabled and it works with Mac OS X v10.1.2.

* Compatible with Windows 2000, SP4, XP and Vista, Certified Windows 2000 and XP
* U3 smart enabled on Windows 2000 (SP4 and later) & XP
* Enhanced for ReadyBoost to boost system performance with Vista
* 8GB capacity, backward compatible with USB 1.1, retractable USB connector

Sandisk 8GB Cruzer - $19.99 via: SD