Dropbox, the cloud storage outfit, has spent something like a reported $100 million in cash and stock pushing Yahoo and Facebook out of the way so it could buy a little 14-man e-mail management start-up whose early-stage widgetry, out maybe a month, can’t really scale so couldn’t meet initial demand and is thin on platform support. It’s also got a lot of features left on its to-do list.

The company it’s bought is called Orchestra, which has what appears to be a promising e-mail sorting program for mobile devices called Mailbox.

Terms weren’t disclosed but leaked everywhere.

Mailbox is supposed to have “redesigned the inbox to make e-mail light, fast and mobile-friendly.” Users are supposed to be able to swipe messages to their archive or trash; scan an entire conversation at once with chat-like organization; and snooze e-mails until later with the tap of a button. Reports indicate that some features work better than others.

Still Mailbox said in a blog that it’s delivering 60 million e-mails a day. And since a reported 1.3 million people are waiting in line to get it, Mailbox is expecting Dropbox to help it scale, which begs the basic question whether Dropbox is really going into the e-mail business despite claims of keeping Mailbox separate.

So far the widgetry works on iPhone and Gmail. Mailbox’ ideal is “inbox zero” and CEO Gentry Underwood says 30% of Mailbox users empty their inboxes every week.

In November of 2011 Orchestra raised $5.3 million in A round financing from Charles River Ventures, SV Angel, Kapor Capital and CrunchFund at a reported valuation of $15 million-$20 million.