I read somewhere (probably on the forums) that if there isn't much difference in price, even if your car is relatively low value it actually is better to keep comprehensive and collision, the reason being, if you are in an accident that is NOT your fault, the only motivation for your insurance company to get reimbursed from the other guy (if they won't admit/accept liability) is if THEY are out the money. If you have no comprehensive and collision, it's no skin off their nose, and YOU will be one trying to get reimbursed from the other person's insurance (and good luck with that, you'll probably have to sue to try to get it). It makes a lot of sense, really. I was rear ended getting on the interstate last year, and it took forever for the other insurance to pay my insurance company (they tried to say it wasn't his fault when it was CLEARLY his fault). If I didn't have it, I would have been out not only the deductible, but also the entire repair bill, most likely.
I just re-upped my insurance - I raised all my coverages but put my deductibles to the max ($2500). The difference between this and no comp/collision was literally like $11/6 months or something like that. I am willing to pay $2/mo for the knowledge that my insurance company will fight for me if I am ever hit again.