I'm sure a lot of people are familiar with the copy and paste facility in the subset editor. It allows you to build a list of elements that may come from anywhere within the dimension using the find facility or reorder existing subsets.
One trick that I don't think people are aware of is the ability to copy from Excel into the subset editor.
e.g. someone sends you a list of costcentres in Excel they need a report on, you can go into your cube, open the costcentre dimension subset, delete any costcentres showing, flick into Excel and copy the costcentres, flick back into TM1 and paste into the subset editor.
This certainly is quicker to build a list of elements than going through and selecting them one by one with the find facility.
The other cool thing is that it will display any alias you have switched on too.