A bit pricey, but a great player.

I got a mini through one of those early spam emails. I didn't think I would actually get one, but I was able to convince 5 friends that weren't signed up for eBay to join, giving me enough referral credits to get a Mini. Of course, they stopped running the program that way soon after I got my iPod (I think they figured out that getting people to sign up for a free eBay membership just wasn't cost-effective). So, although the iPod does cost quite a bit more when you compare the specifications to one of the 20GB iPods, I can't complain since I got it for free ;-) I had a 10GB Archos Jukebox that I had been using for just under 2 years, and I also used one of the Belkin Tunecast II wireless transmitters for the car, both of which I tossed after getting the Mini and the iTrip mini wireless transmitter. So, let me get to the real info...

The player really is an example of what an MP3 player should be and what the digital music revolution should be about. It integrates perfectly with the iTunes software, allowing you to easily manipulate your playlists and songs. Since I have about 10GB of MP3s for a 4GB Mini, I use the smart playlists quite a bit. Although with my old player I carried all of my songs around with me, I've found that I really only listen to about 150 songs on a regular basis. With the Mini, I just make a playlist and run with it. If I need more songs, I just add them to the playlist. I'm also selective about what playlists I load, so that helps me keep the storage issues at a minimum.
Downloading songs is a snap, and pretty fast. I use the firewire port on my WindowsXP desktop, which works well. To use the USB 2.0 though, I had to download an update from August, 2004, so you probably won't have USB functionality right out of the box.
In the car, I use the Griffin iTrip mini, which is a bit nicer than the Tunecast II. The main advantage is that the iTrip mini runs off of the Mini's power, so no extra power cables or tons of batteries floating around the car (I've got a Volkswagon Beetle, so space is a premium!). The Tunecast II for me seemed to give a better signal around 102-108 FM, while the iTrip seems to give a better signal around 90-98, so keep that in mind if you are switching transmitters. With the iTrip attached, I get about 4 hours of music out of the Mini (that's with the equalizer settings also turned on, and the battery life is supposed to be longer with that turned off). Of course, if you have the car charger for the Mini, then that doesn't really matter.
The player gives much better quality sound than my old Archos player. Part of that is because the earbuds are of a higher quality. I'm not a fan of earbuds, but until I get to the store, I'll probably live with the ones included with the iPod. The equalizer setting is probably the key factor in getting better sound quality, and with about 40 preset selections and the option to make your own, it's hard to beat the settings for the Mini.
Charging is pretty fast, at about an hour for a near-full charge, and a bit over 2 hours for me for a full charge. Since the Mini starts charging when it's hooked up to anything that will provide juice, you really have to try to get the thing to run down! One way to do it that I discovered is to use the alarm clock feature. It would turn on my iPod and then leave it on until I did something! Since I had forgotten that I used the alarm one night, I kept finding my iPod drained every afternoon before I would go home from work. Once I turned the alarm back off though, things were back to normal.
The Mini also has lots of extras that I didn't expect. It will store contacts from Outlook, it has a few games, you can store notes, and you can still use it as a good old hard drive for moving files.
The number of accessories out there are numerous, but as far as the basic ones go, just hit Radio Shack. Apple wants about $10-15 for a standard Y splitter (so that you can run two sets of headphones from one jack), when you can go to and electronics shop and get the same cable for under $8 (although it won't be that snazzy white that matches the Mini). Most of the other extras are cosmetic, preventing scratches or allowing you to wear on your arm or around your neck. They all seem to run in the $20 range, but I guess if you were willing to shuck out $250 for the MP3 player, then another $20 to keep it looking mint probably won't bother you that much. The only thing that would have been nice is if it had come with the dock connector. Apple seems to live off of its offerings being stylish, so having the dock next to your computer looks a lot cooler than having a cable draped over the top of your desktop (I had to do this because my firewire ports are all in the rear and I got tired of always having to go behind the computer to hook up the cable!). I've seen the dock for $40-50, which is a bit more than what I am willing to pay, so I think I'm just going to tape the connector to the side of my desk and call it a day!
Anyway, if you can get one cheap, it can't be beat, even with the small storage space.