How blinds work.

It's my understanding that the system for Hold 'em is that the button travels around the table to the next person to the left of the last person who had the deal.

The person to the dealer's left then puts in the SB and the person the the SB's left puts in the BB.

Now, I don't know if there's some finesse to this rule that I haven't heard; but on Everest Poker, at least at their free, limit tables the button frequently jumps to an empty chair or the SB is hopped over.

For instance twice this morning I was in a position where I was the BB and there was no SB.

This is a bug right? This is against the rules?

The button and SB are determined by the BB. The BB always moves left to the next available player. If the BB busts out on a hand (or leaves the table), the SB is the empty seat on the next hand. Similarly if the SB busts out, the button will be the empty seat, in effect making the same player the button on two consecutive hands.

No player should be allowed to skip the BB, and this is the fairest way to ensure that.

Unforunately, on some sites, when the bb leaves the table the button jumps, and some do miss their bb.

Funnily enough something like that happened to me last night, not long after I posted. I was still paying more attention to the forums than the table, so I'm not sure how it came about, but I had posted the SB when it was my turn for the BB. I think it may have been the real SB choosing to sit out instead of posting.

It should never happen in a tournament, though.

It does in stars mtts. Great if you're shortstacked and you miss the bb.

There are two different methods to handle the way a button move when players bust out/leave the table - 'dead button' and 'moving button'. Different sites use different methods

you can read about the two methods on
http://www.homepokertourney.com/button.htm