PCB = US$20
Panel = US$25
assembled = US$220
10 stage Phaser/Flanger based on the Aries 329. It has 11 matched NPN pairs (BCM847) and a set of matched FETs. It is actually quite simple to match FETs, a circuit will be given in the build guide. Pretty much all surface mount, not suitable for beginners!
And a nice demo from Modular Addict, who supply full kits for these