I'm actually sitting on a huge pile of vested options at a company I left a few years ago, but I'm unlikely to ever exercise them during a sale because the strike price is almost guaranteed to be higher than they're worth.
I also know quite a few folks working a big startup sitting on lots of options, except the startup is on something like a G round of financing so they're likely diluted to worthless. Most of them started working there right out of college and don't understand how it works, and the company salary caps employees...it's a cool place to work but they're likely to get screwed if they're ever acquired/IPO.
One thing I've learned after working at quite a few startups as a non-founder is this, ignore the options and try and get the best possible salary you can. If you get some options, that's cool, but don't count on them for anything.