My Titanium PB 400 died recently. It has a brand new battery, 512 Mb RAM module and I'm sure some parts are usable, such as the screen. I don't know why it won't start up any more but I decided not to fix it and bought a new one. It will start occasionally. I spoke to some dealers who suggested that the motherboard was gone so too expensive to be worth fixing.
Anyone in the UK interested please let me know or it's going on a skip soon.