AlexCreates - Offers several free image manipulation programs. Some of the tools create seamless Perlin textures. (Windows) - http://alexcreates.googlepages.com/downloads
Iris - CineGraphics - A quick easy free utility for creating a variety of seamless textures maps. Create thousands of textures by combining fractal noise, waves, horizontal and radial offsets and color gradients. Creates procedural texture maps that can contain an unlimited am - http://www.cinegraphics.net/product.php?location=Iris
Seamless Texture Generator (STG) - Create seamless textures from existing pictures. Also includes highlights and shadows removal, crop, rotate and perspective correction. - http://www.seamlesstexturegenerator.com
Texture Maker - Seamless texture generator and designer featuring more than 130 generators and 700 presets. (Windows) - http://www.texturemaker.com
Tile Builder - Photoshop plug-in for Windows to create seamless patterns. Patterns can be saved as BMP, JPEG or PNG graphic files. - http://www.imageskill.com/tilebuilder/tilebuilder.html
Nonparametric Texture Synthesis - Fast texture synthesis by nonparametric Markov Random Field (MRF) modeling, source code is provided, plus many free textures. (Windows) - http://www.texturesynthesis.com
Genetica - Node-based seamless texture editor that comes with over 500 finished texture presets. - http://www.spiralgraphics.biz/
Images Generator - Program has tools, which traditionally are used for drawing and editing images. The feature of the program is innovative functions for creation images including 3D images. - http://www.imagesgenerator.com
Imagelys Picture Styles - Generate seamless textures, 3D modeling textures or desktop wallpapers. Includes image manipulation tools, filters and masks for transparency effects. - http://www.imagelys.com/
Gliftic - Create 2D designs that can be used as backgrounds for Web pages, as well as wallpaper and book covers. Also generate random designs, includes zooming and tiling capabilities, and to create thumbnails. - http://www.ransen.com/Gliftic/default.htm
UVMapper - Full featured texture mapping utility for the creation and modification of UV coordinates for polygonal 3D models. Planar, box, cylindrical, spherical and polar mapping. Can also completely remap a Wavefront (obj) model, or generate texture map templates - http://www.uvmapper.com/
TextureMagic - Bitmap editor to transform pictures into seamless textures. Offers plenty of effects and filters. (Mac 8, 9 and Mac OS X) - http://www.artissoftware.com/texturemagic/
Paurex - Programs for texture creation and generation, as well as screensavers: Image Styles, Seamless Factory, Script Magic, Work Performer, Digital Waves and Texture Processor. (Windows only) - http://www.paurex.com/
PhotoSEAM - Full-featured image editor for creating seamless photo realistic textures and tiles from digital photography, or from scratch. Anything that you paint, clone, or retouch, automatically becomes seamless. (Windows) - http://www.mediachance.com/pseam/index.html
Impact Texture Studio - A tool to create 256x256 textures that can be tiled for 3d modeling, webpages, or other graphics related effects. - http://www.scene.org/its/
Meta Workshop - Multi-functional toolbox, which allows an image to be swiftly and easily turn into a repeatable tile. Tiles can be used as textures for 3D objects. Texture Workshop lets you modify the obtained tile by changing its color, contrast, and brightness, as well - http://www.metaworkshop.com/
XFader - Pegtop Software - Turns BMP or JPG images into seamless textures. Includes tools for fading control, color adjustment, crowd effect, stereogran generation and filters (such blur, wave and relief). - http://www.pegtop.de/xfader/index.htm