MacUpdate is currently offering seven Mac Apps for just $50. The apps are ForkLift, RapidWeaver, Swift Publisher, Marine Aquarium, Xslimmer, MemoryMiner, and Yep. I’m familiar with Yep, it’s a cool iPhoto like application for PDFs which helps you organize and tag them. Marine Aquarium is an aquarium simulator (fun but not particularly useful). RapidWeaver is …