While my temporary Ubuntu installation is nice, I miss Debian a dreadful amount and plan on returning this afternoon.
Desktop: Debian Gnome
Browser(s): Firefox (w/ Adblock Plus, Ghostery and Flashblock), Epiphany, Links2
Music app: Decibel (my new favorite - a minimalist copy of Amarok's good old days)
Text: Gedit or vi
Video app: VLC
Various terminal things: Dungeon Crawl Stone Soup, axel, rtorrent, scrot
Necessary evils: OpenOffice.org Writer and Impress (or LibreOffice, whenever that becomes stable), GIMP