Well, I believe wp guys have got excellence in making things easier for the developers.
Last day, I had a client asking me to do something which will allow him to change the footer text sitewide(for all blogs) on his buddypress based blog network(or social network :)).
I googled it and found something similar, but was a paid plugin(ahh, the membership fee was too much for me to afford for one plugin), so I decided to investigate further.
After Looking at admin-footer.php, It seemed a trivial task.
there exists a filter "admin_footer_text", which allows you to change the footer content. Glad, I could never know, It was so easy.
So, I went ahead and put an option in the SiteAdmin->Options and, yeh, Now the Site admin can change the footer globally.
So here goes the plugin for you:
What It does:-
It allows SiteAdmin to change the footer links/text globally/sitewide on their wordpress mu/wordpress mu+buddypress based site.
How to use it.
Install It like, any other wordpress Mu plugin.
Please note, It must be activated sitewide
Go to SiteAdmin->Options as shown here
Now look for something which says "Sitewide Footer Content" as shown below
Enter the text/html you want, and Click Update options.
wow, you are Done, Now check the footer, It should show the text/html you entered.
Here is a screen shot from my local test system.
Hope you will like it.
Let me know your thoughts/suggestions or anything you want In the comments below.