Ever since the SARS scare, hand sanitizers have been popular and the alcohol-based ones are actually stellar cleansers for smaller things!
I use One Step hand sanitizer for cleaning various things. Not that I care about the brand, just get an alcohol-based hand sanitizer. I’ve cleaned light switches, keyboards, key fobs, small plastic things, and it does an amazing job. Use q-tips and you’ll be done in no time. I prefer the foaming-action ones as you can more easily soak a q-tip in them.
It does an amazing job at cleaning hard stuff off surfaces. I’ve been using it for a few years now and it does a great job.