CougTek
Hairy Aussie
And here is the news source. I originally saw it on OS News.Tonight, I created the world's first sub-5mb bootable, registry editable, command-promptable, usable version of Windows 95. And what's more, you can build the system yourself, if you know how.
(...)
The system uses UPX compression on the main EXEs and DLLs, btw, in case you were wondering...
Imagine how the original MS version of Windows 95 is bloated if the OS can be trimmed down to under 5MB.
UPDATE : the link to the original site no longer works.