UDP, I have a similar attitude, especially concerning the internet.

After a few years of "mediocre above-average" performance (higher than many, but below the best), I too decided it would be an interesting challenge to get a 4.0. Then I realized that motivation was the natural result of genuine interest... so I stopped forcing it. It's been going up ever since because I'm now taking breadth courses of my choosing.

As for becoming tired of it all, mess up your routine somehow. Last spring my computer's hard drive died and I didn't fix it... I went to the library a lot to do work and ended up socializing quite a bit and then that summer I met my duality partner there.

Sometimes you have to make room for opportunity...