Written for Tiles is response to this thread.
The following example uses small textures to synthesize large textures by scanning the smaller texture and attempting to 'stitch' parts of it together.
It comes with 7 example textures including; bricks, grass, metal exc..
Before synthesis you can select your quality-to-speed ratio; using high quality can take several minutes.
Uploaded as both rar and zip.
(unpack the folder before running)