I read some interesting information about 'Frantz' filters, which have apparently been around since the 30s, which use- get this- a roll of toilet paper as a filter element. Now, the initial reaction is bad, but hey- we all use paper filters because they're the best, right? I've heard (from their own site, given) about heavy-duty diesel engines running 500k+ miles with no oil change, just a filter element change and 1.5qt of new oil every 2k miles.
Here's the site I read:
http://bypassfilter.com/faqs.htm
Anyone know anything, or have real-world experience?