Pay-As-You-Play MMORPGs?

grubber33 wonders: "With exciting MMO games like World of Warcraft and others existing, the current monthly fee plans that all MMO games that I'm aware of aren't necessarily worth it for people that don't have as much time to play games as others. For instance, I have about 3-5 hours to play games per week, if I'm lucky. On top of that, I like more than one game but I'm still interested in MMO games. I was wondering what Slashdot thinks about newer MMO games implementing some sort of pay-as-you-play system or at least having that option alongside the current monthly fees."