Multiple users worklists in a single portal window

If your using integrated authentication and using the standard K2 SharePoint worklist web part no it's not possible.  What you can do is use FrontPage to setup a dataviewer web part and query the DB directly. 

-mike

As Mike@K2 stated, the no out-of-box K2 webpart does not support this type of scenario.

However, if you are willing to write your own webpart you could acheieve this type of functionality with the bleneded use of the K2ROM and K2MNG APIs. 

You can use K2ROM to surface the actual logged in user's tasks (which is what the standard K2 webpart does).

You can then, programmatically, connect to K2MNG as a K2 server admin to retrieve worklist items for other users (called 'Destinations' within the K2MNG API call.  If you want the logged in user to actually action other people's worklist items, the K2MNG WorklistItem is not actionable.  However you can programmatically reassign/redirect it via K2MNG to the current user, then open that worklist item via K2ROM and action it.

HTH