Out of my last two gallons of spent fixer, I extracted almost an ounce of silver. That's a bit over $30 worth. I'll probably generate that much more by the time summer rolls around. By this time next year, I'll end up with that much again. If I keep going at this rate, that'll be almost $100 a year. That's enough to buy a brick of film. You can't beat that with a stick!
BTW: Even after I extract the silver, I'm still going to take my spent fixer to Haz-Mat Collection Day when it comes around again.