I am excited about a completely free program I recently found online called Lilypond, but when I try to explain it to people, somehow no one seems all that enthusiastic. Lilypond is a musical score creation program that takes text-based input. Looking at their website, you can see their focus is creating very precise scores that are not subject to the small annoyances that most computer-generated scores contain.
The main reason why it's got me excited is that it creates a MIDI file along with the score, so I can listent to the notes I've input. As a non-musician, this is very valuable, since it's the only way I can check myself to see if I've entered the notes correctly.
Since I discovered the program about two weeks ago, I've been entering all the songs we've invented throughout the years. These include "Amanda Jean", "Elena Reid", "I'm the Foxy Dog", "The Trash Song", and "Deery in the Cornfield". I'm right now working on trying to convert Richard's (my brother-in-law) composition "Wedding Waltz" that he created for his wedding. It is hand-written (but clear), so it will take me a while to create.