When you drag down in the Android browser to view your tabs, there's a box at the top showing how many tabs you have open. My wife has a habit of checking the weather via the widget which opens a browser tab, then hitting the "Home" button instead of "Back". This leaves lots of open tabs.
Apparently the box showing tab count only supports up to two digits, because when she had more than 99 tabs she got this:
Apparently the box showing tab count only supports up to two digits, because when she had more than 99 tabs she got this: