Let's just hope that the new guy with 2 posts knows what you're talking about then, eh?
Vividwire, you need to right click on the Yahoo! Widget Engine application and select 'Show package contents'. This will show you the 'guts' of the application as a folder. There you will need to navigate to Contents/Resources and find the file called 'MenuBarIcon.png'. Open this in Photoshop (or something similar) and delete everything leaving just an empty transparent layer and save it.
After relaunching, the Yahoo! Widget Engine's menubar icon will be nothing, but there will still be a gap; you should make it your last startup item so it doesn't show.
Hope this helps.