Not sure how captainhook455 is viewing it, but I have seen pages where the page-covering ad fails to work properly on a phone, and can't be closed. I'm sure similar problems can happen in any environment, but I've sen it most frequently on phones.
__________________
_________________
|...............| We live in the nick of times.
| Len 17, Wid 3 |
|_______________| [pics]
|