The Pattern Maker is on a website called Colourlovers. In here, you have an option to make a pattern from scratch with its set of tools or you can also search for custom patterns that other users have already created.
What's nice about the Pattern Maker is that the patterns you make are all seamless, very helpful when you're applying the pattern as a texture on a large area. You can save the patterns as a png file or image file for free and the resolution of the images are very generous. You can save it to up to 1600x1200 image resolution.
What I actually did was search for some of the nicest patterns other users made with the Pattern Maker and used it on the fabrics of my 3d rendering.
You can also have your patterns printed out to fabric with the website's partners if you like.
Colourlovers is not only for pattern making actually and has a lot more online tools to offer, including color matching and creating color palettes for all your design needs.
So if you are a designer - from interior designers, architects to fabric makers and digital artist, try using Colourlovers' Pattern Maker now and I'm sure it'll make your lives easier.