Standing at the edge of the lake, a fisherman saw a woman flailing about in the deep water.  Another man was standing on the shore screaming for help.

The fisherman ran over to the man.  "Help!" the other man started, "I can't swim!  My wife's drowning!  I'll give you $1000 if you save her!"

The fisherman jumps in the water, swims powerfully out to the drowning woman, puts his arm around her, and swims back to shore.  Depositing her at the feet of the man, the fisherman coughs up water, then says, "[cough] ok, bud, where's my 'grand'?"

"But, this is my *mother-in-law*!"

The fisherman reaches into his pocket with a frown and says, "Just my luck.  Ok, how much do I owe you?"