LMMS-Linux Multimedia Studio
One of those MIDI- didi do-dads.
This program is the open-source answer to Fruity-Loops. It can record, digitalize, and create MIDI sounds, mix and master, and can be used as a DAW (digital audio workstation.) Don't let the name fool you. It works on Linux and Windows. It would probably work in Mac with a little configuration. It came as a source code so I had to compile it. I used Gcc compiler for Linux. Version 0.4.8 of LMMS seems to work flawlessly.
It's really hard to impress me with open source software as well as proprietary. I've used maybe 30 sound recording/mixing programs. This one is very cool and easy to use. I created a MIDI sound file with it within minutes that contained violins, cello, piano, and drums. Now don't get me wrong, the MIDI files they use are not the best around, you may want to import your own. It's easy enough to do. The last thing you want is some cheesy song that sounds like a generic Motorola ringtone from 1998.
The program also supports and ships with LADSPA, and other effects. Most open source effects will either ship with it, or be easy to install as plugins. In the first ten minutes I had found the virtual MIDI keyboard, added reverb, compression, and gain. It was that quick.
Don't shy away from free software. Just because it is free does not mean it does not work well. OpenOffice makes a great free replacement for Microsoft Office. If you don't want to or cannot shell out $299 for the full Fruity Loops package, this is the answer. The LMMS home page at sourceforge.net has a 'donate' button though if you are a professional DJ or composer and want to give back to these very talented programmers. Some of these guys are giving their free time like nights and weekends for this project.
I mentioned before that this is version 0.4.8 that I am using. This program is still in beta, yet it runs very well as is. If many people download it, it will only encourage the developers to continue. I tried a program that inserted real-time guitar effects into a live sound of the guitar. The project went down, and there are no developers on it. Not enough people downloaded it. They got discouraged and quit.
So, to wrap this up, I'd like to encourage the DJs out there to make sure you have a C compiler, and some good bandwidth to download it, and have at it.
Download LMMS- Linux MultiMedia System
- LMMS - Linux MultiMedia Studio
LMMS Homepage. You can download it, and the wiki is here as well as a forum for users.