Hot answers tagged set-database
Yes there is! Rebrickable.com is dedicated entirely to doing so. You can save time and import your LEGO collection from Brickset.com (If you have an account). The site will then search for other sets and MOCs you can build from the bricks you have in your collection.
If you want to know if you can build a certain set with the parts you have, you can have a look at set inventories on Peeron or BrickLink You can also even enter a list of your own parts on Peeron and have it check it against existing sets, thus letting you know what you can build, or what you need to buy to build the set you want.
Brickset has a data mining page which sorts sets by certain factors including new sets, unreleased sets, most minifigures in a set, best/worst price ratio and best British pound to American dollar exchange rates. The sets with the most pieces can be found here.
There are quite a few individual sites out there offering that sort of thing, however one of the best I've come across is: The MOC pages on Rebrickable.com This is because the site allows you to catalogue all your parts and then search for other sets and MOCs you can build with your existing collection.
I wasn't able to find anything like this, so I contacted the admins of the sites that I mentioned in the question. Rebrickable was kind enough to send me a dump of their set inventories under a Creative Commons 3.0 BY-SA license, which basically means that you can do whatever you want with the data as long as Rebrickable is acknowledged as the source and you ...
The Unique Brick LEGO Creations provides pdf instruction files, for a fee; but they don't seem to carry sci-fi creations.
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