Easily add 'Now Playing' to playlist

Is there a way to add the song 'Now Playing' to the On-The-Go playlist while it's playing, without having to browse out to the album where the song resides? It just seems strange to me that you can't just click and hold the centre button while you're "On The Go" and it isn't convenient to be playing around with the iPod too much.

Sorry, I know that sounds whiney, but I've been wondering (and grumbling) about it for a while and had to ask the experts.

Thanks a lot,
Mike