Magnus is a simple screen magnifying glass. It nicely integrates with X11 desktops like MATE or Xfce (probably with others not named here, too).

Given the available bandwidth, bandwidthcalc determines how long it will take to transfer a file of a given size. You can specify the available bandwidth in kBit/s, kByte/s, MBit/s or MByte/s. The time output is in HH:MM:SS

mail-expire is a tool which scans mail folders (Maildir or mbox files) for messages that are older than given maximum age and moves them to another (compressed) mbox file or just deletes them.

msort-gui is a frontend for msort utility. It is helpful not only to those who find a complicated command line difficult to deal with but also to those unfamiliar with the finer points of sorting.