I'm sure Jeff is an ok guy, but depending on what work you're after and where you're located, it will likely be sporadic and low-paying. Basically, the low-ball gets the work. I've seen work orders for wiring of demarcs (sp?) for $50-75, plus you never see what the winning bid is when one is "No Longer Available". You used to be able to. OnForce figured that one out, so that you as a "worker" can no longer use this as a rule of thumb to make bids in the future. General PC work/DSL installs usually go for $35-50, but IMO isn't worth messing with, especially if they want you to drive 50 miles to do so.
And, if the work order is any "good", it will be snapped up faster than you can reply to it yourself (bots, perhaps?).
For extra income, sure; other than that, IMO, not so much. Just do your homework when you accept a call; you may find that the company who has the call is slow about paying, or has other issues.