The Nokia N82 comes with a cable for composite TV-out, plus stereo audio. It will even rotate the on-screen display automatically, just as it does on the phone (although this appeared not to work in some cases).
When combined with a Bluetooth keyboard, this makes a very usable mobile computing platform, as the phone also has built-in WiFi. I can imagine it replacing a laptop in some cases. The display is clear and sharp. For it to be a truly usable travel platform e.g. for working in your hotel room, you would need to ensure a TV that has composite in though. As more hotels provide advanced flatscreens, this may become less of an issue.
I'm writing this review using the technology right now. N82 with provided TV-out cable, Dell W2600 LCD flatscreen with composite-in, and iGo Ultra-Slim Bluetooth Keyboard.
After entering all the text, I will have to go on my computer and add in the photos and links, I haven't tested how much of that is possible and easy using TypePad Mobile.
I'm using the N73 keyboard driver from the iGo support site (it takes many layers of clicks to find it). There is no official N82 driver but the N73 Stowaway Universal one works fine.
The keyboard is quite usable, the keys are pretty much full-sized and in the regular layout. You need to use function keys to access numbers, the keyboard only has the three rows of letters plus a function/spacebar row. There is a Bluetooth keyboard driver available from Nokia (mostly to support Nokia's own keyboard offering) but it doesn't provide all the necessary functions - whereas with the iGo driver I can access the left phone selection item with the "windows" key on the keyboard, or with left Fn and the left side of the spacebar if I need to select, similarly left Fn + right spacebar for the right function selection, Fn+K for the main screen, and Fn+C for the "menu" of applications. Fn+Enter functions when you need to make an on-screen selection. These are all marked on the keys.
I looked into adding a Bluetooth mouse, but these are not supported. Not really necessary since you can just use the up/down/left/right arrows on the keyboard.
The keyboard folds up in to a portable, closed case.
In addition to dedicated apps like the TypePad Mobile example shown at the top of this posting, you can also just use the built-in web browser and apps like the mobile version of Twitter.
I wish apps actually gave more control over fonts, as the browser display you can see fits a lot more text than the TypePad Mobile screen, and even that app shows more text on its status screen
Overall I think the cellphone using WiFi plus TV-out with Bluetooth keyboard make quite a usable mobile solution. The keyboard does also have a stand so that you can use the N82 propped up in front of the keyboard, but I think that would be a lot less usable for anything more than very brief messages.
UPDATE 2008-03-22: Apologies for the multi-postings, apparently every time I sent from TypePad Mobile and it told me the send failed, it was actually queuing  it up somewhere. Images and links
to follow later today have now been added. ENDUPDATE