This console application shows you the list of running workflows in Sharepoint sites /Site collections; you can specify if you to visualize all running workflows or only faulting workflows.
To use the console application (on the sharepoint server) :
WorkflowExplorer http://<yousite> all : displays all running workflows
WorkflowExplorer http://<yousite> error : displays all faulting workflows
WorkflowExplorer http://<yousite> raw : displays all workflows (including completed and their raw state, nice fro developers).
Of course you can redirect the output to an ascii file : WorkflowExplorer http://<yousite> raw > mytextFile.txt.
An stsadm extension and a web part are "on the way".
Some screenshots on my blog http://sergeluca.spaces.live.com/blog/cns!E8A06D5F2F585013!5774.entry.