This is a tool widely used at work, thought it might come in handy to others.
Maya's own selection sets seem to be node based and therefore limited to that file, this creates a selection script and saves it to shelf to be used in any file.
"Name" name of button as it appears on shelf. "+" to add selected objects to list. "-" to remove selected objects from list. "Create" to create selection set.
Delete key will remove selected list items from the list. Can use ctrl+LMB to toggle selection sets.
Any ideas on how to improve this tool let me know. It should work on 2008+