ReadyBoost is described as 'Disk cache component of Microsoft Windows, first introduced with Microsoft's Windows Vista in 2006 and bundled with Windows 7 in 2009. It works by using flash memory, a USB flash drive, SD card, CompactFlash or any kind of portable flash mass storage system' and is an app in the os & utilities category. There are eight alternatives to ReadyBoost for Windows and Linux. The best ReadyBoost alternative is PrimoCache. It's not free, so if you're looking for a free alternative, you could try SoftPerfect Cache Relocator or m/prefetch. Other great apps like ReadyBoost are HDDTurbo, GiMeSpace RAM Folder Pro, O&O CleverCache and SuperCache.
I've downloaded and tried it twice. Even following a "how to" video on a 2nd PC click for click I couldn't get it to work.