Streak - CRM in your Inbox. Strange - that thing completely passed me by. Ok, maybe that's because they call it a CRM and that's boring by definition for me. But in reality, it's not a CRM at all, but rather a kind of spreadsheet with mail integration and filters - you can define rules and sort mails into boxes and evaluate, filter, sort all these things according to various criteria, whatever. And the whole thing is integrated into GMail, directly into the web platform (which of course means it only works there and not, for example, in the mobile clients). And suddenly the whole thing is interesting again, because if you deal with larger quantities of email-controlled workflows, you can use something like this well. At least if you have your emails in GMail. Their architecture is also not uninteresting, as they use pretty much everything Google has to offer.