This is a potential security issue, you are being redirected to https://csrc.nist.gov.
Linux Devices.com is a comprehensive webpage with information on current open source coding projects for linux systems, quick references to Linux code in different programming languages, and user/developer forums.
Handhelds.org has quick links to every aspect of programming on PDAs. The site features "How to" files, open source code, Linux release downloads, and easy references to many other resources.
Also at Handhelds.org is the new Linux Familiar release. Familiar now features a multi-user capacity for Linux based PDAs.
For information on the known security issues on Palm powered PDAs and their suggested solutions check the official Palm Enterprise homepage. This site comprehensively addresses user access, server-side security, and anti-virus issues, and also contains a security issues checklist for Palm devices.
Linux Security is a webpage devoted entirely to the security of Linux systems. While it does not focus directly on the security of mobile devices, this site deals in detail with programming in a Linux environment with security considerations in mind. The tutorials and documentation here make this site still useful for device security programming.
Microsoft's Device Management and Data Security Microsoft's Windows Mobile device management and data security pages features information on their device security model and discusses security considerations for protecting critical data.