Building a platformer and are thinking of procedural generated levels?
Gamasutra has an interesting 3 page article up by Cloudberry Kingdom developer Jordan Fisher talks about precisely how he created the algorithmic level design system for his procedurally generated platformer.
Thinking of building a platformer and mulling over editor/engine choices? CDN member Hanclinto has a great platformer application;
Platformer Starter Kit, using the PushButton Engine it allows you to easily create your own flash based platformers with XML based levels, advanced physics, full documentation/source and starting artwork so you can get crackin right away.