LCI Linux sysadmin certification

OK, so here's a set of skills I'd like to acquire: LPI certification. I've been half-assing sysadmin work since the 90's, and I suspect I actually know most of this stuff - but you know, it's all kinda vague.

Spaced repetition (earlier) would be perfect, here, and could also be formatted like an exam simulator (see which).  Questions could identify weak spots and indicate places where tutorial help is needed, and that brings in topic trees and gamification of tutorials (earlier). [IBM developerWorks has some tutorials to start from.]

To all that, add the fact (HNN, WSJ) and you have a compelling story.  Only thing missing is the money. Here are my top-of-head notions:

• Ads (duh) and donations
• Sell books on-site, sell ... other things on-site (i.e. better ads)
• In-depth things paid?  (I don't see how this wouldn't just be arbitrary)
• Sell the tutorial service for other subject matter.
• Offer corporate groups as a thing.

That's what I can think of immediately.  But this is a good overall thing to consider writing.