Great, addictive gameplay makes this free MMORPG a must!
If you want more for your money, though, get a Member's Subscription. Starting at only $4.99, you get an extremely larger area to explore, more armor, many more quests, and so much more. You get 4 more Grand Exchange boxes, more ways to earn money (think farming isn't good for money? Think again!), more bank space, 9 more skills, and so much more! You can play many games against other players, both safe and not.
Now, I know that there are people out there that say RuneScape is lame, and can see where they get that. RuneScape, is actually very fun if you get into it. People say that RuneScape has horrible graphics, but in HD (which isn't all that hard to run), the graphics look amazing. I never play SD anymore.
Overall, RuneScape is a fun, addictive way to spend extra time. You have skills to raise, monsters to kill, and a treasure to make. Try making an account at RuneScape.com and you won't be sorry.
Go Play!