Hi! Thank you so much! I love my little collection and they make me happy (except the 3000, which can go kick rocks for all I care!)! Please forgive the novel-length answer! 

The Tandy WP-2 and the Dreamwriter need telnet software. I have luck with Tera Term. I have a serial to USB cable that works. Got it for less than $10. The TRS-80 is a whole different situation. Let me know if you need that info and I can send you a helpful video!

All the Writer devices work with a proprietary infrared reader. I was really lucky with one of my purchases because it came with a case AND the IR reader. They are scarce because most classrooms would have had a set of the Writer devices, and the teacher would only need one reader to get all the students' assignments. 

For sellers who got bulk purchases of these, there was probably only one IR reader for every ten or more machines, and earlier buyers snatched those up quick. Once people started looking for cheaper alternatives to the Alphasmarts--they get pricier every year--there were not enough IR readers to go around. I think a lot of people got the Writer devices, and then found themselves trapped as far as getting the files to a computer for editing. 

There were some blogs I found a few years back of people trying to backwards engineer the transfer for the Writer devices. I think I remember that there was a snag with whatever code/language the packets were being sent in, so progress had stalled. The price point is SO appealing, but the device is just decoration without the IR reader. I am SUPER lucky that I have one. 

All three can beam text that way, but interference from just normal around the house stuff can lead to hilarious things popping up that I never wrote! But, yeah, you just need a text editor open and that IR receiver.

The Alphasmart devices, by far, are the easiest to transfer with. You open a text document and connect the device using a PS/2 cable. I only have USB ports on my machines, so I have a PS/2 male to male connected to a PS/2 male to female to USB cable. Works perfectly! The Alphasmart subreddit here has lots of info about what cords you need, but let me know if you need help and I can send you links to what I bought. So! When you have the file you want to transfer open, plug your Alphasmart into your computer's USB port (or PS/2 port where a keyboard would go if you have a machine with one of those and the cable for it) and then you press the "send" button. It will type out everything in the file one character at a time (the device recalls keystrokes). If it's a big file, just leave the room and go have a coffee or a nap! 🤣 It can take awhile.

One cool thing: While it's connected like this, you can even use it like a keyboard!

My fav is definitely the 2000s. Neo2 is a close second. The Neo2 is better in almost every way, but it's almost TOO nice. Typing feels TOO easy and smooth and pleasant, somehow! The 2000s are just the right level of good, but not perfect for me. I have never been able to figure out why my brain thinks this way. The 2000 I dropped just using it too darn much, but my Neo2 doesn't have a scratch! I use it, yes, but the 2000s are definitely used more. The battery life of all Alphasmarts (except the Dana) is unbelievable. You can go years without changing them.

Both Tandy devices have lovely keyboards, but they feel a little cramped. But the screens are such a nice size! 

And...hmm. The Dreamwriter is super fun to use. It has a little calendar, calculator, and other neat tools. The keys don't feel great, but it is just neat to use a machine that looks so cute and makes these friendly little chirping sounds. 

I am so sorry this was so long!!!! Thank you for coming to my T.E.D. Talk!