It looks like this:
It is also extremely useful to see the traffic shaping effects when playing around with shaping rules on your Mikrotik router. It uses the Accounting feature of your router.
The tool with basic instructions is attached to this post or you can download it from the links below.
I hope this can be of use to someone! Comments welcome. 
Daniel
PS: I know this is technically not a 'sniffer' but it actually started off as one so the name stuck.
EDIT:
I added a new version to this post (V1.0.3). Download the service and viewer from the links below. I had to split them because the forum does not allow files larger than 1 MB any more.
Change Log:
V1.0.3 (2014-06-24)
- Ability to specify service name
- Use keepalive on service
- Added code to help plink.exe start up the first time
- Added more FAQ's to readme.txt
V1.0.2 (2014-01-15)
- Added ability to track multiple subnets
- Fixed and improved logging for service
- Removed 'Save to CSV' button which was not working
- Fixed typo in readme.txt instructions
- Added some FAQ's to readme.txt
