The irony is that the comments that got me the most karma weren't the ones I considered of highest value. A detailed, genuinely helpful response in a small subreddit might only garner a half-dozen upvotes while a snarky one-liner in a big sub can boost karma by thousands.
Reddit's Contributor Program could earn you real money for your Reddit karma (www.androidauthority.com)
Reddit could be working on a Contributor program, letting top contributors earn real-world money from the gold and karma they receive.