HP has a nice bit of experience with slim phones, and given the recent success of tablets, it is not unsurprising to see HP and Palm investigate this field further.
Unwired View has now undug the following image from a patent filing. It shows a “detachable cell phone” and a PDA:

As of this writing, not much more is known…
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Lets not forget that the foleo was an inherently terrible idea to begin with. It hinted at good ideas to come (The idea of the Netbook) but it was itself quite silly.
Hi med,
I have to admit that I like this idea.
I have met many people carrying PenPhones from haier in the past – sometimes, you simply don’t want to carry that heavy phone…
All the best
Tam Hanna