BleachBit deletes junk to recover disk space and maintain privacy. It rids your system of old junk including cache, Internet history, temporary files, unused locale files (better than localepurge), logs, and cookies. Designed for Linux systems, it wipes clean 50 applications including Adobe Reader, Bash, Firefox, Flash, OpenOffice.org, Opera, Real Player, Skype, and more. It shreds files so that they cannot be recovered, and it wipes free disk space to hide insecurely deleted files. It offers both a simple PyGTK GUI and a command line interface for automation.
MojoMojo is a Web2.0 wiki with AJAX live preview, hierarchical structure, tags, diffs, pluggable syntax, permissions/ACL, attachments, RSS feeds, a photo gallery, edit conflict resolution via 3-way merge, themes/skinning, localization, built-in full-text search, and a reverse index. Since it's built on top of the Perl Catalyst Web framework, MojoMojo supports any Web server, and includes its own standalone one. It also support any database backend supported by the DBIx::Class ORM, and has been successfully tested with PostgreSQL, SQLite, and MySQL.
claws-mail-indicator is a simple plug-in which adds support to Claws Mail for the Ubuntu indicators. Notifications are displayed in the Messaging menu, with the option to display a notification bubble each time new messages arrive. It was developed and tested on Ubuntu 11.04 (Natty) 64-bit.