I tend to prefer names that are uncommon in english speaking countries. I usually go for european names (especially scandinavian and italian names) but occasionally south american, asian, african. though that's not to say I don't like regular names too - after all, my favourite sim is called John York, which is about as dull as it can get. Admittedly the last name York isn't so dull but it's definitely not the most interesting. Most of the time I search websites like thinkbabynames, babynamenetwork, and (if I'm really despairing) babynamegenie for names.
Some names I'm using at the moment that I really like are:
Ernest (or Ern)