I live midway down the long hill where the road slopes, then levels, and slopes again for several iterations.  The trouble is that the topography creates blind spots for drivers taking the road.

There is a crossroad two properties away from our driveway entrance.  My neighbor's daughter was about to make a left turn at the crossoads which is at the bottom of a slope.  A Jeep Commander has slowed down behind her to make a right turn.  Two cars at the bottom of the slope after a level part, making it difficult for the traffic that followed to spot them, but stoppable in most cases as long as the drivers are within 35mph limit posted.  However, they were unlucky as the young female driver, apparently busy with her cellphone and coming down evidently at 50mph or so down the hill didn't see them in time and smashed right into the back of the Commander which then pushed the Jeep forward and bumped into the Neighbor's daughter's Civic.

Turns out she was driving with an 'international license' most likely expired and most likely uninsured. Her car, no offense to iNeon but a Neon slipped under the Jeep and the whole front end was flattened.  The Commander seemed to have sustained no damage upon one look but I'm sure it's rear suspension and underside must be a mess.  The Civic had rear bumper pushed in and rear quarter panels pushed out to the side.  Luckily, nobody was hurt but when I arrived at the scene two minutes after it had taken place and found out what had happened, I had nothing but to give the girl a dirty look as it was entirely her fault as she was speeding and paying no attention to the road ahead.  There was absolutely no skid marks at the accident scene.  I was further inflamed by the fact that she was an uninsured driver - this coming a week after an 18-yr old uninsured, unlicensed illegal alien smashed into the house of my daughter's teacher's house - but let's save the illegal alien issue for another forum.

I am nervous whenever I need to make a turn and there is an idiot tailgating me with phone in his or her hand.  I don't care, I actually slow down to a crawl well before making a turn so that they are forced to slow down before I make the turn.  I can see them cursing over the phone and pointing at me (funny how people gesture to their conversation partners over the phone) but it's the only way to keep these idiots from slamming into the back of my car asI need to come to a stop or to make a turn.

Does anyone have any constructive deterrent to tailgaters (other than to pull over and let them pass) and people whose attention is diluted because of their cellphones?

If you hate for tailgaters is passionate, then so will be this solution. Rig up your windshield washer to where you have REAR facing spray nozzles. Fashion them into your rear bumper and mix a solution of Joy Dishwashing detergent and water (half and half). When they get too close, spray their ass with the thick viscous liquid and when they attempt to wipe it off their windshield, it will smear causing them to have to pull over or, better yet, wreck, killing everyone inside!

Um, have you actually tried this??  

You can probably adjust the aim on your washers without relocating them btw... of course they would then be useless to you otherwise, but it would be a lot easier...