This might be a lot of work.. probably would be, but I'll ask anyway, and draft out basic functionality for if you'd like to take it on..
So what I'm thinking, is to have the clipboard store data instead of overwriting it, and then have a method of accessing previously copied items as a duplicate of the Show Desktop icon.
Waving the mouse over it would bring a box with a list into view that can stretch all the way up the screen, where you can see thumbnails of image data, parts of text if too long, or just the active application's name if ambiguous data (e.g. a 3d model in Maya or something).
Clicking any item on the list would both make it the active item (so re-copying but preventing a duplicate on the list), and close that list view.
But if you actually clicked the button rather than did mouse over it, the list stays up when you click something, until you hit escape, click the button again, or perhaps click the header of the bar, which would be quite wide so as to easily click.

Options would be:

Show Multi-Clipboard icon
(  ) Right of Show Desktop
(  ) Left of Show Desktop
(ticking one unticks the other)

Multi-Clipboard icon width
[   ] (Pixels)

Multi-Clipboard icon colour
[[]] (swatch opens system colour picker)

Maximum Stored Items (leave as 0 for unlimited)
[   ] 
Notify when full
( )

Maximum Visible Items (leave as 0 for unlimited)
[   ]
(this could be used to limit the height of the bar, but another option to do that could be used instead with a scrollbar, perhaps that might be better..)

Maximum Clipboard storage (leave as 0 for unlimited)
[   ] (Megabytes)
Notify when full
(  )

Clipboard Storage Directory
[...] '------------------------'
(mouse over shortened name would tooltip the full directory)


Anyhow, that would be totally awesome if you did make it.. there are a few multi-clipboards out there, but most of them have irritating flaws, like not going away when you want them to, or being so old they have compatibility issues, and not one of them has any kind of awesome integration into the taskbar.
So yeah, there's my concept anyway, and you're free to do whatever you want with it, and thank you for an awesome piece of software! =)

I wanted to share my suggestions I have offered in past...
Here it is:


The following suggestion I suggested for VistaSwitcher, but it is also true to 7TT:


I would love if Taskbar Inspector will become a kind of Advanced Windows Manager.
Stamimail

I would like to get a feature which would allow users to choose their Language Bar language by left clicking the taskbar while holding the Ctrl button. By default Windows uses Left click + alt + shift.

I just update my version of Clover http://ejie.me/ and now when 7+ Tweaker tries to load it says "cannot attached to Explorer process" and does not load correctly. The Window opens but the Options dont affect Windows. I like your application a lot and would to continue using it in conjunction with Clover.