Don't just limit it to Infantry weapons, there's other sources of armament that gets forgotten about - light AA guns and aircraft/helicopter weapons.
Both the Rhodesians and the South Africans mounted 20mm cannon taken from aircraft onto vehicles, a practice started as far back as WW2 when the Long Range Desert Group mounted Vickers K machine guns on their jeeps and Chevvies.
It can still be seen in the "technicals" in Africa and the Middle East with such installations as single and twin barrel ZSU-23 systems mounted on the back of trucks. The 20mm German cannon in the 2nd Ed. Heavy Weapons book would be a good choice.
Given what's been seen in Libya this year, helicopter rocket pods are not out of the question and maybe even the turret & basket from a BMP.
Edit: Hmm, I see BoogieDownDonovan posted similar ideas as I was typing my reply. And he has links!