Throwing the Kroggs aside, I've recently completed my Zanatorian Interceptor Swarm. For the model I use Forge World's BFG Dreadclaw assault pods, which work pretty well for a swarm of small robots. Quite cheap too compared to other models. Too bad they are hard to photograph effectively due to their size.
Anyway these guys represent my Scarab swarms and as the name suggest they job is to intercept combat units before they hit my line and take the bullets for more important units like the destroyers and warriors.
So what'ya think?