I'm worried about falling gas prices

My SUV has a pretty big gas tank (150 litres), and I don't drive it much, so I don't need to fill it up often. It still has about 100 litres of gas I bought three weeks ago at $1.38 during hurricane Ike, and it's gut-wrenching to know that my $138 investment is now worth only $109.

My neighbour has made a modest proposal to buy this gas from me before its value drops any further. What do you think—should I take him up on it?