I've been planning to buy Kevin Smith's New Jersey Trilogy,- Clerks, Mallrats, Chasing Amy and probably Dogma. There's even a slipcase box available for the first 3 films, in Kevin Smiths website viewaskew.com or graphittidesigns.com.
A box set isn't available since, the 3 films are distributed by different companies, the most expensive of which is Clerks, released by Miramax, costs at about USD39.00.