MIDIs are the only way I know how to make songs, and I've accumulated a couple dozen MIDIs of my own (very amateur) compositions. They're not fleshed out songs but rather short and simple ideas, which is why I like to call them "musical notes".
Here are some of the ones I like best:
Happy And Safe
One of the better songs I came up with while playing on the black piano keys only. There's a key change at one point, which may or may not sound cheesy.
And All That Before
Breakfast (2012, 2014)
An "all's well that ends well" kind of melody. It's a lot better than what I usually come up with, and I can't shake the feeling that I subconsciously stole it from somewhere. The chords to it are simple, but I'm proud I found them!
Very little going on here other than atmosphere, but it came out surprisingly well. This song was eventually ported to the Super Mario World format and intended to be an underwater theme in A Plumber For All Seasons, but it ended up unused.
This song was eventually ported to the Super Mario World format and used as the credits theme in A Plumber For All Seasons.
Working title: "JZ" (2014)
This one uses a blues scale, probably without me knowing what that was. I'm still not sure where the idea for the melody came from — all I know is it's a mess in the MIDI editor.
Working title: "CH" (2014)
This one's in 5/4 time. I'm pretty happy with the melody and the harmonies in what could pass for the chorus.
Good Job (2015)
A slow buildup to what I think is an alright melody. The bass line closely resembles that of "JZ", which is on purpose as far as I can remember. I completely forgot where the name came from, though.
Working title: "DE4" (2015)
This one's basically just alternating D and E chords underneath a melody they never asked for. The part near the end is a 4/4 version of a piece of "CH".
City Lights (2017)
There's not a lot to this one, but I think it sounds positively "dark" and "cool", for lack of better words.
Working title: "NT" (2018)
This is another one where I found the chords on accident. It sounds like it wants to be an intro from an old-school RPG or something.
Baby Steps (2021)
For this one I was deliberately going for out-of-key chords that sounded interesting. I have no idea what exactly I did, and I don't know if the chord changes are sensible or just gibberish.