I must warn you. There will be models which do not agree with lead-loving miniature fans in this post. Don't choke on your tea.

I've resently tried Cyberfire (another Crossfire clone) and I find the game truely inspirational. It makes you think tactics in a new way in wargaming imo.
I've started a Cyberfire gang based on Canids (GW Orks with Wolf heads), but this thread will be about my own little project.
Mechfire where platoons/lances of mechs and their support elements combat each other using modified Crossfire rules.
A Platoon/Lance of mechs and their Command vehicle (platoon leader):

A decimated tank squadron on the move:

The Company commander oversees the battle from his Helicopter here protected by mechs:

A Scout Mech lurks through the streets of the city:

Artillery:

Battlefield (needs some work and mending):

If you're not a fan of paper mechs you could field Battletech, Mechwarrior Clix or any kind you want really. I just find great pleasure in building these bad boys out of paper and cardboard.
/Jaeger