Emulating things with connectivity is also an excellent way to get the project sued out of existence. I'd avoid iPods until The Steve comes up with something better, and phones for current GSM/CDMA networks until those technologies are retired.
Which iPods though? Apple pretty quickly likes to regard iPods as obsolete and replace them with newer models... and quite a lot of suckers buy into the constant upgrades (on the other hand, I know someone who still has a second-generation iPod).
It's a fine line, considering that even iPod Video is considered obsolete and old by Apple.
I don't know what really would go into emulating an iPod... the hard disk's firmware is quite easy to copy (dd if=/dev/sdc of=file ...), but there's also a fail-safe firmware stored in ROM that might be difficult to dump, i don't know for sure.