FYI really .. I have all errors switched on on IE (I need to ...) I get a javascript error from the site now every time I open a topic .. only started happening today I think
Sounds like a problem with one of the adverts on the site.
I'll keep an eye out for it, but if you spot that there is always one particular banner/mpu on the page when it happens then please let me know, it'll help me get it sorted as soon as possible!