I first saw the box for Descent: FreeSpace sitting on the shelf of a neighbor who had introduced me to the Descent series, but I thought it was just some weird spin-off thing and didn't really ask questions.  (Not having the Internets at the time meant that I couldn't look it up myself...ah, youth.)  I didn't think much more of it until I bought Descent 3, which had an ad for FS2 on its fold-out disk sleeve.  The little blurb about huge warships and these strange "Terrans/Vasudans Shivans" sounded interesting, so I kept it in mind.  I guess I eventually wound up picking up FS1 when I came across it in a store, and I was obviously immediately hooked.  (My younger brother used to be my "copilot" while I played, watching me and yelling out updates on things like hull integrity. 

) I later wound up re-buying the game just to get the included Silent Threat expansion...maybe not the best money I ever spent, but whatever.  
Due to the ridiculously-high eBay prices, it took me a very long time before I was able to get my hands on FS2; all I had to tide me over was re-watching the trailer (can't remember which game that was included on...Descent 3: Mercenary, maybe?), playing the demo (must have gone through that several times), and gleaning random info from posts here on the forums, which I was lurking by that time.  It wasn't until Interplay announced their 20th anniversary re-release that I was finally able to get my hands on it...for $50, compared to the current $6, but that was 
cheap then. 

 Needless to say again, I was hooked even harder than I had been with FS1.  It took me a lot of waffling before I plunged in and attempted to get FS2_Open up and running, since the installation process wasn't nearly so well-documented as it is now, but that eventually worked itself out too.  (Good old 3.6.7...you crashed so often.)  Obviously enough, I've been hanging out here ever since.