Who can make an FOI request?

Below is an extract from a recent (3 Mar 2009) ICO opinion, case
reference ENQ0234673 that I have been forwarded. The opinion suggests a valid request for information under the Freedom of Information Act 2000 (FOIA) as an 'applicant' is a request which:

"* “is in writing,
* states the name of the applicant and an address for
correspondence, and
* describes the information requested.”

The FOIA does not seek to place restrictions on who can make a request for information and thus the word 'applicant' is not defined within the Act. An 'applicant' can be a private individual, an company or any other body such as an unincorporated association."

This appears to be quite a liberal interpretation of who can make a request under the Act but it may reflect what the ICO does in practice. Up until now I had assumed that the ICO would only accept appeals from natural persons (people), companies, limited liability partnerships, public authorities and bodies formed by statute, Royal Charter or similar. I thought that only 'legal persons' could make requests.

It would be great if the ICO could publish some guidance on the website about this.