Depends on what I'm doing both on the Mac and real world - and which widgets are live. There are days when I seem to hit it every hour or so and there are days when in late afternoon, I open it and the weather widget refreshes from the night before.
Widgets I've found myself using are the translator (instead of making a vague one in my head from context or skipping it), the BugMeNot lookup (rather than just avoiding the site), the train schedule (because it's marvelous!), the Su Doku (since it means I don't have to finish it in one go) and the Notepad since it takes up less screen than lots of Stickies.