I needed a pixel font that was optimized in space but still comfortably readable, so I created Simpixel.
As three by five (3x5) seemed a reasonable size for capital letters and numbers (cf. A, B, E, S; 2, 3, 8 etc.), I tried my best. This didn't always work, as particular letters naturally need more horizontal space (cf. M, W; N, Q), such that some ended up four or five pixels wide (Though I have created a monospaced version - Simpixel Mono - where I managed to also condense those letters to 3x5).
I then worked on the small letters and eventually the rest of the Latin and even the Greek letters, just for fun. Of course, the less basic letters tend to be larger in size. Emoticons, pictograms and miscellaneous symbols fall into that category too (cf. ½, ⅓, ⅔, ¼, ⅛, ⅜, ⅝, ⅞, ⅟, etc).
With all that being said, thanks for checking this out!