One obvious one is making micropayments both possible and frictionless.
If people got into the habit of making a small reward for a good blog article (for example) because sending 5c or 10p to someone was as trivial as dropping the metal equivalent into a coin tray (see http://YouTube.com/user/MultiBitOrg
for an example screencast), then it would:
a) drastically change the presentation of those websites - site owners would have more cash to improve design
b) reduced advertising and affiliate cross-selling as an income stream - site owners no longer operate at the behest of advertisers
c) coupled with OpenId this could act as a micro-subscription model so that a tiny amount buys you enhanced access for a long time - no pestering for payment
d) this may promote more people to make their income online since the barrier to entry is much reduced - less commuting and office space
e) payment could be optional with the site owner relying on a few good seeds to support the leechers
Clearly all this could be gamed.
Sites could introduce paywalls to block access to content that once they were forced to make free. However, if sites got into the habit of making drivel expensive then they would see a corresponding drop in revenue as people went to other competing sources and spent their coins there instead.
In my experience if people are offered something for a fair price then they are largely prepared to pay it, but they punish hard for being ripped off.