I bought a PDA for use with my job then discovered I could use it for SatNav... it had never crossed my mind when I was looking for one. The whole caboodle cost me
HP2210 PDA with extras £160 (ebay)
TomTom Software £10 Ebay
Cradle/charger/speaker £29.99 (ebay)
Holux Compact Flash GPS reciever £44.00 (ebay)
Extension GPS reciever £9.99 (ebay)
Total £253.98
Also have speed camera data base installed on TomTom from www.pocketgps.co.uk
Also have 15 CD's in MP3 format on SD card in PDA that plays through cassette adapter into cars sound system. Brilliant !! It would hold more but with my autochanger I find that 19 CD's are enough...and where could you find a 15 CD changer!!
The system looks like this.....


Food for thought maybe.........