glynor, you actually import your offline media into your main library database?
don't you find that doing that queers some of your smartlist results etc? or do you just add a [removable]=0 to your rules?
I do actually, but as I said, mostly with my video files. Typically when I compile an entire season of TV shows, or a handful of XviD'ed movies (recorded perfectly legally with my DVR App of course)
I burn them out onto DVD-R. You can usually fit about 1 full season of shows, recorded in beautiful quality, on 1 DVD+R DL.
Anyway, I add these files to the library, and use MC to manage the discs. I name and number each of them when I burn them, and then this shows up as the Volume tag in the files. Under each Video-Related viewscheme I have a duplicate view scheme (easily created by drag-dropping the VS into itself on the tree and choosing Copy) called "Local Only" that adds [Removable]=0. It shows up right under the regular view scheme (even in ones that are "Populated" right at the top where you want it) and works just like it's parent but filtering out the removables. Works from Theater View too!
I generally keep that "search" in the Top Parent categories (eg. Audio, Imports) of my View Schemes where I don't want to see the Removable stuff.
I also use the Removable support to assist in cataloging and backing up my images. I work in a "Multimedia" department at my job (graphic design, video, animation, A/V, and Photography) and I manage a large collection of photographs. I also live up in Maine and a big part of our Photography needs involves taking pictures while outside playing (hiking, kayaking, and whatnot) so I'm encouraged to take a bunch of pictures all the time (yeah, I know, poor me).
Either way, I have about 60 GB of 5, 7, and 12 MP JPEGS in my online collection right now, and about 20-30k more archived on disc (not to mention all my audio and video personal stuff). It keeps them nicely organized, searchable, and tells me which disc they're on when I need them. If only MC had an OSX client, a real Library server, and user management! (I'd have gotten my company to buy it for all us graphics grunts).