The best thing would be how easy the 401K plan is as well as the approval process for time off. While its not unlimited time off, the company takes care of its employees.
The best part of the benefits was the ability to work from home once a day. I can not say there was anything about the benefits package that I did not like.
For a startup, they have a pretty terrible benefits package. The health insurance mostly covers doctors in Pittsburgh but not in California (where they had an office). You get 3 weeks of vacation but no sick days, so if you don't feel well you have to take a PTO day (can't work from home). They give out pretty old hardware to work on, and there's no budget for snacks or food.
Management is constantly trying to find new ways to reward people and make sure they enjoy themselves. They go through the same struggle every SMB is facing in having to get their insurance rates requoted regularly to avoid the carriers increasing the rates dramatically each year.
List based on reports from current and former employees. It may not be complete.