Get daily builds of the new Ubuntu 13.10 distribution here. Saucy Salamander will be the next and best release of the Ubuntu distribution yet.
http://cdimage.ubuntu.com/daily-live/current/. Daily builds page.
64-bit PC (AMD64) desktop image. PC AMD-64 image.
PC (Intel x86) desktop image. PC i386 (32bit) desktop image.
64-bit Mac (AMD64) desktop image. x86_64 bit desktop image for a Macintosh.
Texas Instruments OMAP4 (Hard-Float) desktop image. ARM USB image for machines with an ARM CPU.