VPN
From Openmoko
You need the module tun, check if it is still available with modprobe tun or download the modules for your kernel.
VPN for a ARM CPU is available at http://www.angstrom-distribution.org search for VPN. I use the vpnc_0.3.3-r2_armv4t.ipk[1]. Install it with opkg install [filename or URL]. Edit the default configuration file /etc/vpnc/default.conf.