tom (tjv) sells a similar set up for the Big Green Egg at ceramicgrillstore.com called the Spider..
Not sure how many people cook with woks on Webers but it certainly could work or maybe start a new craze !!
XL BGE (#2) & Performer Platinum
Former owner: Jambo Backyard, Klose BYC, Lonestar Vertical offset w/ Insulated Firebox, Medium Spicewine, Pitts & Spitts, XL BGE (#1) & (2) Medium BGE's, 22" WSM & (2) 18" WSM's, 18" & 22" Weber Kettles