Sam's ears are getting a little slouchy, so I picked up one of these yesterday:
Amazon.com: Oster Cordless Pocket Trimmer: Pet...
It's fairly quiet, and doesn't make that loud snap when I turn it on. I haven't used it yet, just let it run while he sniffed around it. He's so squirrelly about any grooming, it'll be interesting to see how he does with it.