If you spend a lot of time in the back yard in the summer chances are you spend time fighting mosquitoes. You can buy citronella candles or if you follow this tutorial from Garden therapy you can make your own for a lot less.
I like that she uses empty cans because I love to recycle and any time we can reuse something that would go in the trash is a good thing.
http://gardentherapy.ca/diy-citronella-candles/
Yaley 9 Inch Pre-Waxed Small Wire Wick with Clip-6PK
Milliard Natural Soy Wax 444, 10 LB