Although my houserules can be referred to easily on a single sheet of paper (i.e., use d20 Modern, "Shadow Stalkers" campaign model, reference to my gun rules, my chase rules, the Madness rules, Incantations. and E6) my houserules aren't really that short of a document if I actually put all of the texts of most of those modules in one place. I recently did so, referencing all of the text of all of the rules except those that are specifically part of the MSRD. I thought this was a more convenient place to house them.
I still think it's more to swallow at one time than many gamers would prefer, but for that, I've got the summary above. This is the more inclusive document that, along with your copy of d20 Modern, and your character sheet, I'd expect most gamers would actually bring to the table with them.
Anyway... for the heckuvit... here it is.
EDIT: Link got moved. The wowway service was cancelled.