Waterproofing IPod?

Hey guys, 
I like to run in the rain a lot, however I am worried about my IPod being damaged. I have an older IPod Nano, and I do have waterproof earbuds. I was wondering if anybody had any ideas on how to waterproof it, or make a waterproof casing. The biggest concern is the large charging plug in on the bottom. I have looked for waterproof cases, but I did not see any that fit my needs. Thank you for your time and help