I have a Google account that I keep permanently logged in on two computers + an android phone.
On one of them I get signed out every one or two days, while on the other I'm signed in all the time (unless I log in or the cookie expires - once a month or so).
I've checked the account activity (the bottom link in Gmail) and there are no signs of weird account activity; it's got traffic just from these two IPs and my mobile.
Has anyone else experienced weird log-offs like these? Is there any particular reason why it may behave like this?
Update I just noticed this: while I'm experiencing the logout of iGoogle in my Chrome browser, I can go to Gmail (by entering the address in the address bar) and I'm logged in.