Just got myself a copy of LMMS (a free open-source music making program.) Now I am able to make musics like 123! Nyan Cat is so 2011, but I did this just for fun and sharpening my music making skill.
I used a lot of LMMS's plugins like TripleOscillator and some sound samples of kick/clap/and mats and rims.
Please contact me if you would like to use this in a project. We can discuss the details.