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Assigning permanent drive letters to USB drives on Vista

For various reasons you might want external storage to come up with consistent drive letters. For instance I use Unison to backup my data to two external HDD, both of which connect with the letter f: when plugged in separately. This confuses Unison's state and it ends up taking a long time to synchronize the roots. It would be better if they came up as, say, f: and g:, so I could write two separate profiles for them.

Dave from the unsion users list pointed [thread] me to USBDLM. This runs as a service and enables one to do a host of things with removable storage drives, including assign persistent drive letters. But, it is not opensource and it is a service.

Reluctant to add more services to my list I found out that Vista's Disk management system, which allows you to rename drive letters, is persistent. Which solves the problem elegantly. I think. So far.

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