Here is a Half-Life skin that I made for the HALO Warthog when I was bored. There are two lamdba symbols on the hood if you look closely. I was going to put the Black Mesa logo on it but there werent any good spots to place them.
http://i26.photobucket.com/albums/c102/HondaKid95/HLWarthog.jpg
http://i26.photobucket.com/albums/c102/HondaKid95/HLWathog2.jpg