I like the DS, and the DSi will probably be worth it, even though it's not that much of a difference between this and the DS Lite. A Korean company called GamePark Holdings is coming out with a console called the
GP2X Wiz, with an SD card slot / touch screen (Yes!). I have the previous version, and it was actually pretty good; it ran PS1 games at a rate of, oh, 5 FPS.

This one, though, will have a 3D Graphics Accelerator, so PS1 games may not be impossible at a smooth frame rate.