Chronos is a Web agenda calendar for intranets, although it can be used from anywhere. It can send reminders by email, and it allows you to schedule multi-user events. It is fast and light on resources. The balance between size and speed can be tweaked by tweaking mod_perl and Apache.
QuadKonsole is a terminal application that embeds Konsole kparts in a grid layout. This saves memory, provides faster startup, and makes it unnecessary to align your Konsole windows by hand. It also provides a lot more screen real estate, makes navigation easier by using arrow keys, and allows all Konsoles to minimized or maximized at once. It only occupies one slot in the taskbar.