Some of the Irish ones are crackers (in both senses), although they're not necessarily just fiddle tunes.
A few examples off the top of me head: Johnny With the Queer Thing,
The Cow Ate the Blanket, Pull the Knife and Stick it Again, Old Hag You Have Killed Me, Up Stairs in a Tent, The Pope's Toe, When Sick is it Tea You Want?, The Unfortunate Cup Of Tea, Fasten The Leg In Her, etc.
John Kelly