ChemLab is a Minecraft mod targeted to increase SMP experience by overhauling and adding mechanic to create different types of survival activities for players. This mod is not recommended for SSP until you want heavy challenge to be on your way: at least more than one player is advised.
This is all about processing materials and creating advanced autonomous stuff, effectively progressing through tiers. ChemLab Tiers are not the same as in the other ore doubling(tripling) mods - by each tier you get access to more ways to process various resources flexibly changing outcome of your industrial empire.
Important: Check setup notes in the my last post on official forum thread!
Latest Minecraft Forge
Both CL and CL Coremod + CL Addons(check mcf thread)