I am currently having problems with my website in IE (non-compatability mode): http://www.cueprojects.ca.
When I switch to compatability mode the page looks fine.
Two problems are: the navigation sub-menus are pushed over by apx 75 pixels, and the news scroller text does not become hidden and overflows the entire page (even though css property is set to hide).
Attached is a screenshot of IE non-compatibility mode:

and how it should look like (in IE compatibility mode and FF, Chrome)

This is a problem because you didn’t position your ULs correctly.
To make sure they’re positioned below their ‘parents’ you should make the LIs they are in relative with
position: relative;and secondly applying the styleleft: 0;to the ULs. IE has quirky behaviour when you don’t specify the positioning explicitly.I don’t know which exact bug this is but I would advice you to avoid IE8 and below like a plague (or at least IE7, which is pretty much not used anymore).
Next to fixing this, you should still use the X-UA-Compatible tag as either a http header or meta tag in html.