Gmail Docs & Spreadsheets

I enjoy the Spreadsheets integrated in Gmail very much (the docs part is not that great to me; perhaps it's just difficult to do all those edit functions online, and mathematic formulas are relatively easier?) However, I can't find the option to include a Docs & Spreadsheets file directly in an email, although it can be downloaded or published in blog or shared with others. Whenever I appreciate something about gmail, I'll miss rainred a lot... Time flies, and it's almost five years since I know these good friends...