Following in the footsteps of A9 and others, Google has finally put out a product that allows you to view and manage your search history from any computer. It is currently in beta at www.google.com/searchhistory/login.
Some initial thoughts:
Google SERPs change so often these days that returning to a previous search may not help you find what you were looking for.
This is yet another way for Google to track user behavior, which they may use in their ranking algorithm (judging by the patent application that came out on March 31).
Sounds like a cool idea, but I seriously doubt I will use it much, if any. Check it out for yourself and see what you think of it.