Straight from a thread at the SPUG.net forums, Ddeath documents his conversion of a Treo 650's antenna into a shorter form, using off-the-shelf components.

In honestly looked like an amateur job in the beginning, but this probably stemmed from judgementalism. Eventually, when finishing was applied, it only needed a few modifications to blend in seamlessly.

It seems that "Hollywood"/"Lennon" mania is strong in Palm's fans. The new, antenna-less model is rumored to be first released in Europe under Vodafone.