Another tried and true quick-money, little hassle contest is the "Guess How Many" one.  Simple fill a large jar with, for example, several different sizes and types of dog biscuits.  The contest is to guess how many are in the jar.  Use a variety of brands and sizes because if you fill a jar with all one size, or even all one type but different sizes, it's easier for people to estimate the number. 

Come up with variations on the theme, using different contents for the jar.

People will need to pay to enter the contest - $1 is probably fair.  

Create posters, run an inexpensive newspaper ad, get some free radio time, etc., to advertise your contest.  Make a fairly large, highly visible, display around the jar to attract people.  Provide slips of paper with space for name, address, phone, and guestimate. 

What's the incentive for people to enter the contest?  You be the ruler here.  Solicit for a donated prize - a good one - like a DVD player, tickets to a big-city theater, a $100 shopping spree at a local retailer.  Ask and you'll receive.  Post the prize, or a certificate, near the jar of bones as further incentive to enter the contest. 

Specify that a person may enter the contest as many times as he or she wants, but that each entry has to be paid for.  Enter ten times and they pay $10.

In case of tie, hold "Guess How Many" tiebreaker on-the-spot between the finalists.


Jar of Bones