The Si5351 is a beautiful family of chips, appropriate for generating all sorts of useful frequencies, particularly the -C variant, which can take an external reference clock.
Trouble is, the package is a bit awkward to work with. A minimal breakout, with some filter caps and maybe pads for input attenuation, would be a sweet way to get started developing something more serious.
Who wants this? SDR folks, for one! Everyone with a cheap RTLSDR has discovered the awful wander of the on-board clock. The '51C is really ideal for taking another stable reference (of whatever frequency is convenient) and synthesizing the 28.8MHz used by the SDR chip.