Homemade baby wipes - I did cloth baby wash clothes in the warmer as baby wipes with both my boys but with plain water. Easier than cloth diapers and I still feel a little bit more eco friendly. The solution with tea tree and olive oil is a great idea too.
This is a spectacular example of how to set up a reusable baby wipe system! I would just make one small change - substitute those disposable diapers for some eco-friendly cloth ones! The warmer pictured is a Prince Lionheart Warmies Wipes Warmer - it works great!