Global Custom Blog Fields / Per Blog on MU

Good morning all...

I saw somewhere along my 'searching' something relating to 'Global Custom Fields' but can't find it.

What I'd like is to have a few fields per blog that the super admin can edit, that can be called within each blog. As a temporary solution I have an 'include' file per blog that holds a few variables that are needed for each blog and I call them within the custom theme files.

The system I'm developing integrates with another system and these variables are required on the fly to ensure the integration is smooth and can't be broken by the blog user/admin.

Have you come across something that gives the 'super admin' the ability to enter 'custom blog fields' in a MU network?

Cheers.

Martin