Arachne is program that implements Avidan and Shamir's seam carving technique for content-aware image resizing. It allows realtime, fluid image resizing using this fascinating technique. Seam carving works by removing the "boring bits" from an image, so it can change the aspect ratio of many images without changing the shape of the objects inside.
Grafx2 is a bitmap paint program that allows you to draw in more than 60 video resolutions (from 320x200 to 1024x768, including most of the standard Amiga resolutions: 320x256, 320x512, 640x256, 640x512, and more, provided your video card knows how to handle them). Its layout is not very different from the famous Deluxe Paint or Brilliance, so it will be quite easy to handle it if you know at least one of these programs.
MuseScore lets you notate and compose music easily with your keyboard, your mouse, or a MIDI keyboard. You can print beautifully engraved sheet music or export it as PDF or PNG. You can play your score, transpose it, and save it as audio or MIDI file. MuseScore also supports MusicXML to let you share your composition with other scorewriters. MuseScore is often advertised as a cost effective alternative for Sibelius and Finale.
bed is an adjustable data format binary editor. Data formats are ASCII, unsigned and signed integers, float, bit-flags, bit-fields, labels, EBCDIC, and time_t. Different sizes and byte orderings are possible. Data types can be used in structures. Other data formats, filters, and procedures can be defined in plugins. It features copy, paste, undo, redo, search, replace, marks, record/play, and context sensitive help. bed can be used to edit raw hard drives. Under Linux and FreeBSD it is even usable without the X Window System.
neXtgen Povray Editor (XPE) is a graphical editor for Povray based on wxWidgets library. It looks like a modern code editor (like Kdevelop, Netbeans, or Eclipse) but is focused on Povray. It is organized to optimize work space and includes numerous features (nearly all those from Povray's Windows version and many other extra features).