I am setting up a system for inventorying all our project windows. I have it setup to log the project name,window name, and last opened date/time.

Is there a way to get the storage size of a window in a project?

I thought this might be useful for finding windows that have huge datasets in them. This would help us keep our project size down.

Thank you,

No, there isn't anyway for you to currently do that.

A bit manual, serialize it in the designer. This would give you a relative size. Anything over a certain amount or if it suddenly jumped it size could a red flag to look deeper at the serialized XML.

If you SHIFT-Right-click on a window, you can see the window's size under the Window Info entry.

Or in the raw settings viewer, this query will give you your window sizes.
SELECT name AS Window_Name,
bit_length(data)/1024.0 AS Window_Size
FROM project_resources
WHERE resourcetype='window'

Obviously, use the raw settings viewer with EXTREME caution. If you mess up your system, you won't get any sympathy from the techs over the phone.