Hurray,
after a long wait, I have accidentally discovered how to minimize realplayer whilst playing a realplayer video, audio or streaming file (ie: bbc iplayer)
Instructions, for N95 8GB at least:
Close your handset, lock the phone using the power button menu.
Unlock the phone using the left then right selection keys, and after doing this quickly press and keep your finger on the multi-tasking key to bring up the task manager. You can then select standby, and your realplayer audio/video/streaming will continue to play!
However: the reason Nokia clearly never implemented the ability to minimize realplayer is that you may experience stuttering, particularly when streaming, every time you do some intense task which relies upon accessing the in-built phone memory, such as accessing your message inbox. You will find things pause sor a split moment, but resume again nicely once things have loaded
Anyway, better than nothing, right? Well done modest me.