I had just started actively playing computer games when I played MotS demo, liked it instantly, got the games yadda yadda yadda... but even though I kind of fondly reminisce their SP campaigns themselves (not much to talk aboot today but I won't deny playing through them like a million times in 1998-1999 and 2001-2003), the maps on Massassi (and TACC... and JKOutpost before those) were what really made those games great for me. HL may have CS and other mods that have thousands of people playing them, but it never had extremely cool and even a bit funny SP levels like Birth of a Mercenary, Leeza's Destiny, A Pirate's Tale, etc. Or maybe it did but that's really beside the point.
I'd figure I'd still be playing those from time to time rather often-ish if JK and MotS only worked properly on my comp. Of course they aren't graphically excellent, but it's still funny how great they are in the wake of endless CS clones and GTA wannabe level projects that are made for modern games. Correction, projects that get concept art and weapon renders posted on their bloated homepages with proper downloads every 5 years or so.
Good times... that said, I only have legal copies of DF, JK and MotS - no boxes either... man, I really should have kept those back in the day. Oh well. I also got the audiobook versions of the DF books back in the day, only listened to the first one... I don't remember it being that good, but at that point I finally realized where AKPiggott had got stuff for his BoaM storyline from