Here's my version: NO! You should always get something in return for your hard work.<p>Of course, in a few cases on there, you ARE getting something for your hard work (or repaying favors you already got), it's just not cold, hard cash.<p>Any trade that isn't in balance is bad for both sides. It may not be immediate, but it will be eventually.
Perhaps this is overly simplistic, but by definition "work" is stuff I wouldn't do for free.<p>I definitely do technical things for free, but I'm free to walk away any time -- I think the essence of "work" is the inability to walk away (without terminating whatever contract is in place).