Again, the wonderful StephSim has allowed me to host some of her sci-fi walls and floors – 468 textures in total! 
Most of these walls and floors have previously been included with different lots, but they have never been released as a set before.
I’ll let Steph do the talking:
“Note: The walls and floors in the Sci-Fi Mega Sets were created under the name “stephanie b.” (the name I used prior to adopting StephSim).
Sci-Fi Mega Wall Set
This set includes 300 select General Sci Fi Walls from the various Sci-Fi sets created over the years. Location and cost of textures in this set vary.”
Click to View a Slideshow of the Sci-Fi Mega Wall Set
“Sci-Fi Mega Floor Set
This set includes 168 select general sci-fi Floors from the various sci-fi sets created over the years. Location and cost of textures in the set vary.”
Click to View a Slideshow of the Sci-Fi Mega Floor Set
Of course, Steph has provided us with collection files for this set as well. 
Note that these files goes into your Collection folder, and not into your Downloads folder.
Note: While the 300 walls are in one set, Steph has divided the collection files for the walls into 3 sets of 100, for ease of use when redecorating.
ALL Collection Files for the Sci-Fi MEGA Set Textures – for PETS and above
ALL Collection Files for the Sci-Fi MEGA Set Textures – for PRE-PETS
Thank you, Steph!
Shane Peltzer said,
May 7, 2012 @ 16:33
Ooh very cool! I would definitely use these for my Inventor Sim in his high-tech house with all his robots. Thanks for sharing Nix!
NixNivis said,
May 7, 2012 @ 18:08
Aren’t they great? I’m so glad Steph let me host them.
I love how you can use these walls in so many different settings – sci-fi, modern, techno… Me, I had some of them already, but not all, so I’m thrilled that Steph has released them as a set. But between them and the B5 walls, they have my poor Downloads folder groaning in pain. 
(“Did you just install over 900 walls? Are you insane?? How can you do this to me?!”)
Shane Peltzer said,
May 7, 2012 @ 19:08
My downloads folder is always growing and groaning lol.
~*~stephanie~*~ said,
May 12, 2012 @ 07:47
Shane and Nix….
LOL!
I’m giggling. When I decided to share this collection, I was overwhelmed. There were literally almost 2 thousand textures. But, I wanted to pick and choose my favourites to share, so I cut it down to a few hundred instead! In the process, I wanted to “improve” them…but decided to just leave well enough alone.
Hopefully, you both can select your favourites and set the rest aside. YEAH RIGHT! Good luck with that!
At any rate…Do enjoy the textures!