Information/Fun/Misc Freeware Utilities :

1. convert units of measures : units
2. find word meanings and synonymns : gnome dictionary
3. see 3d space simulation : celestia(-gnome)
4. solve a scientific calculation : galculator / rcalc
5. solve equations and plot graphs : euler
6. zoom onto the Earth from space : google earth

This is a list of tools that are available in, at least, Ubuntu 6.10 (Edge Eft).

Graphics/Images/Photographs Freeware Utilities :

1. convert images into various formats : gimp
2. create a flash-based animated how-to/tutorial : istanbul (only to theora ogg)
3. create a web photo album and slideshow from my photographs. : gthumb
4. create icons : gimp / gnome-iconedit
5. create thumbnails of images : gthumb
6. draw charts/graphs in 2D/3D from data : OpenOffice / gnuplot / plotdrop
7. draw diagrams : dia
8. edit an image : gimp
9. find the color of any pixel : gimp
10. magnify image to pixel level : gimp
11. manage galleries of photographs : gthumb / f-spot
12. paint creatively : gimp
13. paint creatively (for kids) : tuxpaint
14. pick a color from a pallette : gimp / agave
15. remove unnecessary information from a jpeg file : exiv2
16. stitch together multiple photographs : gimp
17. view images in an album folder : gthumb

This is a list of tools that are available in, at least, Ubuntu 6.10 (Edge Eft).