Hi,
i remember i once had music, the files were super tiny but there were so many tracks in one single music file. It was kinda weird. You could also skip tracks in Winamp etc but it was still the same file.
It was some kind of chiptune music i think.

Does someone know how those files are called?

mod files can do that, midi of course. but best guess is mod or it was spc with a plugin

I think i found them, they are Ataris SAP Files.

But thanks spike for reminding me about good old SPC files too

Mod is not small enough.
There are other ways, but I don't know then in detail.

Search for "Farbrausch", they use stuff like this in their demos. I think there was also revealed HOW they are achieving this.

You can also give SID (C64) a try, but it's plain chiptune.

Ohh it is SID!

I thought it's SAP but they rarely have multiple songs in one.

Thanks so much, downloaded a SIDPlayer and the music. Great!

They had great music on the C64.
I used to compose on the Amiga using The Mod-Tracker format.
Although they used Samples, it was still quite small songpackages.

Midi also still stands. Its the perfect format for small
mobile games. If you have to keep under the 300kb limit.
..for the whole game...

Great music on C64 -> leads me to SID Synth:
http://www.ucapps.de/midibox_sid.html