Google's 20 Percent Time Projects Pay Dividends for the Rest of Us

eWEEK offers a visual peek at Google's famous 20 percent time projects. These include Gmail, Google News, Google Talk, Orkut, Google Sky, Google Moderator, Google RechargeIT and Google Grants. What is your favorite of the bunch?

Aside from the college dorm-like aesthetics, on-campus meals and other perks Google's 20,000 or so employees enjoy, Google is known for some other customs that differentiate it from the mass of other high-tech companies.
One of those is the 20 percent time project rule, which allows programmers and other Google employees to spend one of their five work days per week working on something of their own design.

See Google's 20% Time Projects Here

These projects stay in-house for awhile, but several have been spun off for use in the outside world. Do you know which Google products or features evolved from the 20 percent time rule? Gmail, Google News and Google Talk are among that number.
Here is an expanded list of such projects, along with an image of the product or feature. What is your favorite 20 percent time project or tool from Google?

What tools or features would you like to see from Google that may come as a result of this rule?