they are probably the hardest thing to get off after tar. But - if you take a roll of paper towels - your kitchen variety - and lay them across the front end and lightly sprinkle with a hose(or spray bottle) until the paper towels are soaked - then do something for about 10 minutes - wash the windows, dust the dash, check the tire pressure, oil, etc - then remove the paper towels - those little dead and hardened critters will mostly pull up with the towels, and the rest you can just kind of wipe off with the wet towels at that point. Works great and relatively inexpensive. NO harm to the finish and easy on the pocketbook.

2001 Classic Red Mazda Miata (+/- 30MPG)
1998 Toyota Sienna (+/- 23MPG)