It's dangerous to slow down without using your brakes (with lights to alert the tailgater) and also to slam on your brakes.
A military policewoman i knew told me that if you lightly tap your brake with your left foot it makes the brake lights come on, without you actually braking. You can also, if possible, use your right foot to accelerate away. I've only done that in a big merc though, my wee hatchback probably couldn't handle it.
I once had a tailgater pulled over by police behind me, during a campaign against tailgaters, which was satisfying. I tend to either pull over if i can or put the 4-way flashers on to buck up their ideas.
As to not driving to the road conditions - if you are driving at 30 in a 60 zone with no reason (ie. the conditions are good and your car is ok) that is sometimes as dangerous (mostly because of the reactions of other drivers you are holding up unnecessarily) as speeding.
But tailgating is twat behaviour.
I was tempted once when the bint following me for 20 minutes was hard up my arse alternating between doing her make up and using her phone.
Bint? really? get to fuck with the misogynist language.