The "SED" part came from my top three Team Fortress 2 classes by play time.

The Soldier_engie-demo → SolEngDem → SED

Really long ago it was sometimes shortened to TSED.

The "4906" part partially relates to 4096

But it's really just 2¹² with the middle digits in Base 10 swapped.
You may see a lowercase h appended in some places, like Intel's hexadecimal syntax.

You must eat the universe.

Create text in a small (4x6) bitmap font.

Create text in a less small (9x14) bitmap font.

Create text in a very small (1x4) bitmap font. (modified to use RGB color channels)

It's meant to resemble GNU Emacs with the tango-dark color scheme.
I just think it's aesthetically neat, I don't really use Emacs...
(My text editors of choice are Gram and Kate)