grml is a bootable CD (Live-CD) originally based on Knoppix and nowadays based on Debian. grml includes a collection of GNU/Linux software especially for system administrator and users of texttools. grml provides automatic hardware detection. You can use grml (for example) as a rescue system, for analyzing systems/networks or as a working environment. It is not necessary to install anything to a harddisk; you don't even need a harddisk to run it. Due to on-the-fly decompression grml includes about 2.1 GB of software and documentation on the CD. You don't have to pay anything to use grml because it is free software!
Dev Todo is small command line application for maintaining lists of tasks. It stores tasks hierarchically, with each task given one of five priority levels. Data is stored as XML, so various XSLT templates can be executed on the XML to convert it into different formats (eg. HTML).
httptunnel creates a bidirectional virtual data connection tunnelled in HTTP requests. The HTTP requests can be sent via an HTTP proxy if so desired.
This can be useful for users behind restrictive firewalls. If WWW access is allowed through a HTTP proxy, it's possible to use httptunnel and, say, telnet or PPP to connect to a computer outside the firewall.