In the spirit of hacking to make things better(while waiting for Slack to launch their feature...) I bolted on message threading onto Slack. It consists of a two part effort. First using the Slack api to overlay a reference map on to all messages and then secondly, overlaying a UI upgrade onto the slack web client (via JS/dom manipulation encapsulated via a chrome extension).
Conceptually, this means it is possible to also 'upgrade' various other sites/apps that we feel is lacking in some way or another.
Try TalkHq out and tell me what you think!