I still keep a PSION Series 5mx Pro for my everyday agenda, address book and else. (Still looking for a *good* alternative for my iPhone, including migration/synchronisation software - got any?).
The PSION is secured with a 3 letter password (to allow for easy log-in). *ALL* my passwords, credit card numbers, PIN &c. are stored there in an encrypted file. The CompactFlash card of the device holds an impressive 128 MB (yes Meg - not Gig) but 80 Meg remain almost always free. It is regularly backuped to my PC being regularly backuped to my Synology DS-408 being regularly backuped independendly to two 1,5 TB external hard drives. From a previous SDK there does still exist an emulator for PC that even allowed to access the file from there. But last time I used that is ages ago - literally.
As the devices used to be pretty cheap recently, I do still hold 2 spare ones in my drawer for replacement in case of emergency...
Real Users find the one combination of bizarre input values that shuts down the system for days.