Cool gadgets that went (almost) nowhere

[IAMBIC]

Near the top of the list must be the Apple MessagePad (Newton).

Also, I vaguely remember a Panasonic VCR that hooked up to your telephone line (the same way you hook up an answering machine), so that you could dial in and remotely program it to record a TV show. Anybody else remember this?

Any other cool "flops"?