For the ultimate in simply not funny, all you have to do is look at late night television. Mainly Jay Leno, but none of the others are particularly funny, either.
While I agree that Jay Leno is the pinnacle of bad comedy, with Jimmy Fallon nipping at his heels, I will always enjoy Letterman and Conan and Kilborn. I got sick of Conan for a while because for a while they kept recycling the same material with too little variation, but I learned to appreciate him again years later. Letterman's monologues suck, and the Top Tens are never that wonderful, either, but the stories he tells in between the monologues and the first guests are almost always hilarious. The interviews are hit or miss, but he finds the right rhythm with a guest, it can be magical.
