It is quite a viable strategy actually. When programming my AI's for the few shipsets I have made/are making I make the Colonizers all have the 'ram' strategy. The first thing a colonizer usually encounters is an escort when it goes thru a wormhole. The colonizer will ram and usually survive with most comp intact, the escort will usually have most/all weapons destroyed. Instead of the colonizer running/being destroyed it now lives/destroys alot of the time.
Then there is the case of the heavy carrier that has a shipbuilding component and builds fighters with xplosive warheads, basicly uses them as 'missiles'. Nasty in combat when you get hit with heavily shielded large fighters with kamakazie warheads, really makes point defense earn its pay.
I have seen a few other shipsets use the 'ramming colonizer' ploy, at least the Rage did it to me a few games back, surprised the hell out of me, I was ready to board and they just smashed me flat!

Even a non-warhead ship does some ramming damage (not sure how much), so you can either be a target or just ram instead, I have even used this target as POINT DEFENSE, just try using a ship with good shields/armor and ram your way thru a cloud of fighers, 'boooommmm', no more fighters!(good when point defense hasn't been researched/added to ships).
Just my thoughts........someone else will probally think of something I didn't
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"The Empress took your name away," said Chance.
Owen smiled coldly. "It wasn't hers to take. I'm a Deathstalker until I die. And we never forget a slight or an enemy." -Owen Deathstalker.