I have bought lots of laptops for business and a couple for gaming.
If your interested in gaming on a top then look at the Dell XPS.
http://www1.ca.dell.com/content/prod...ref=lthp&s=dhs
These tops are POWERFUL, stable and Dell of course has great support. Keep in mind gaming laptops are HEAVY and not normally suitable for lugging to work everyday unless you have strong arms. They are portable of course so you can take over to your buddies place for a round of HALO.