Ok, this isn't going to be in-depth review, so please don't read this expecting it to be one.  This is basically just going to give you a rundown on what to expect when buying this or any of the generation 5 wifi units(the 605 units, and the 705s)as far as what to pay and the costs of buying one.  Basically, the retail costs of the generation 5 605 wifi units are: 4gig with sd slot(expandable to 16gb) $199.99.  archos is currently selling these with an 8gb sd card included for $199.99 on their website. The 30gig version is $299.99, the 80gb is $349.99, and the 160gb is $399.99.  The 705wifi units are $399.99 for the 80gb unit and $499.99 for the 160gb unit.  These are the msrp prices that came from the archos website.  obviously you'll find different prices from different stores and sellers. 

What everyone needs to realize when purchasing an Archos wifi unit is that the unit itself although supports wifi, you can't actually use the unit to go on the internet unless you buy the Opera browser plug for $29.99.  If you're a previous IPOD Video user, and your video files are in the mpeg 4 format, you'll generally also need to buy Video podcast plug-in for $19.99.  The Video podcast plugin allows you to play video podcasts downloaded from the internet with .mp4, .m4v or .mov extensions, encoded with H264 video codec and sound track in MP3 or AAC format.  Since many of the ipod video files are encoded with either H264 or AAC formats, you'll need this to play your ipod video files.  If you're looking to have access to Web TV or internet radio, you'll have to buy a plug in for that as well-for $19.99.  Then, if you want to watch movies in certain formats(.vob, .mpg and .ps extensions) you have to buy another plug in for $19.99, called the cinema plug-in.  The cinema plug-in also allows you to have 5.1 surround sound through the dvr station.  In order to watch the archos through your tv, you're going to also need one of the docking adapters. 

Their are 4 adapters you can pick from:  the DVR station that costs $99.99, the DVR travel adapter that costs $69.99, the battery docking adapter that costs $49.99, and the mini docking adapter that costs $29.99.  Every one of these adapters allows for charging the archos, USB file transfer to the computer, and playing audio/video onto your tv.  Each of these adapters has it's own benefits and negatives. 

The DVR station for $99.99 basically does everything that you would want-record shows from your cable/satellite box, plays audio/video from your archos, comes with a remote with qwerty keyboard so not only can you type, but you can basically control everything on the archos from it.  It allows you to surf the web from your couch since you can type on the remote keyboard.  The DVR station also allows for component, S-Video, and SP/D connections along with the standard composite connections, and includes the ac adapter to plug into your wall socket.  The DVR station works with the archos 605 and 705 units. 

The DVR travel adapter doesn't have as many connection options, but is only $69.99.  It plays audio/video from your archos, allows for recording from you cable/satellite box, and has the basic composite connections alone, but CAN'T be used with the 705 units.  It doesn't come with the keyboard, and is also lacking the ac adapter, which you must purchase seperately for $19.99.  Basically, with the ac adapter to plug it into the wall, you'll end up spending about $90.  For the extra $10, you get the remote/keyboard and better connection options. 

The battery docking adapter for $49.99 has a built in battery to extend the playtime of the archos 605 units, but CAN'T be used with the 705.  This adapter allows for playing video/audio on your television from your archos with the basit composite cables, but doesn't allow you to record onto the archos.  There's no remote with the adapter, but it does come with the ac adapter to plug into the wall.

The mini docking adapter for $29.99 is the most basic of all the adapters.  It allows for playing video/audio on your tv with composite cables, but doesn't allow for recording onto the archos.  It doesn't work with the 705 units either. 

For people like myself who would are looking to hook up their archos to their head units in their cars, the mini docking adapter is the best way to go.  You just buy the mini adapter, and plug in the rca cables to the back of your head unit.  archos doesn't make an FM transmitter, but there are aftermarket units available to purchase if you look around. 

To sum up everything, for the Archos to work at it's full capabilities, you're gonna end up spending between $50-$200 on the plug-ins and adapters depending on what you're looking to do.  Basically, for everything you want to do on the unit, you'll have to pay.  Archos is banking on people spending the money on their plug-ins and different adapters, which will push the price up significantly.  Be aware of this when you look to purchase an archos.  I own the unit, along with the DVR adapter, and have purchased a bunch of the plug-ins as well.  In all, I've spent probably another $150 or so since I bought the unit.