vpnd is a daemon which connects two networks on network level either via TCP/IP or a (virtual) leased line attached to a serial interface. All data transfered between the two networks are encrypted using the unpatented free Blowfish encryption algorithm with a key length of up to 576 bits (may be downgraded to a minimum of 0 bits to suit any legal restrictions).
vt-ng detects virus and worm like activity based on communication patterns. It can be used to detect infected hosts within your internal network and stop the spread of malware. Detection is based on the fact that malware usually tries to initiate many connections to the outside network for various reasons, such as to "phone home", download further malware, or scan the network for other vulnerable hosts.
vzhaipd (scoyo's Virtuozzo/OpenVZ HA IP Daemon) is a set of mount/umount Container scripts for Parallels Virtuozzo or OpenVZ that will make sure a HA IP is always present on one of two or more Containers. You can think of it as the poor man's VRRP for Virtuozzo and OpenVZ Containers. Use it for general service availability, software load-balancer failover, etc.
waproamd is a Linux WLAN roaming daemon for IEEE 802.11b cards supported by a driver with the wireless extension API. It may be used for configuring WEP keys according to the WLANs available. It is intended to be used in conjunction with ifplugd, which configures your network automatically whenever an association with an AP succeeded.