It is definitely a pretty good investment, but I feel it's worth it. I'm on my second iPod now (gave my first one, a 5GB, to Jenni), so that should tell you something. Once you have it, you'll know it was worth the money.
But, if you don't have the money to spend, you can't really get one, either. I recommend the 10GB model @ $400. You can fit about 2,000 songs on it at 160KBps, it's about the size of a deck of playing cards, pretty light, runs for about 10-12 hours on a single charge... and you can put songs onto it at a pretty quick rate
The navigation is really efficient (it's hard to stress how well this works - that's why I <b>strongly</b> recommend you play with one before buying) and... it's cool. There, I said it.
Plus, you don't have to carry around a boatload of minidiscs and whatnot. And the 32MB buffer gives you ~20 minutes of skip-free joy.
Hey, here's another thing - the display is amazing. If you get to play with one, here's a fun trick - hold it up close to your face and put your hands around it so it's really dark. Then hold the menu button (top part of the circle) for ~2 seconds so the backlight comes on. Man oh man. <b>Everyone</b> I have showed that to is impressed.
Nowadays, when I buy a CD, the first thing I do is rip it - and then stick it back in its case and toss it on a shelf. I never go anywhere without my iPod, and it's pretty much all I listen to music on.
And hey, if you're a university student, the 10GB is only $369. So that always helps.
If you have any more questions, go ahead and ask me. I've got no problem going on and on about probably my favorite toy