This is a merb application for tracking one's consumption and waste, build on merb. It's not a terribly complex application and is nowhere near complete.
The idea is that you can keep a record of consumption by adding "items" to "reports". Not great names, but I don't know what else to call them. Reports are by-day and are summarized for the user by-week.
Items might be like "drive to store" which has a usage of 10 (miles) and impact of 0.5 (gallons). This can be automatically calculated if the user creates a "metric" (again, not great names) called "car" (maybe more specific if they have multiple cars) with usage unit "miles", impact unit "gallons", and ratio 0.05 (20 miles per gallon, which is actually 0.05 gallons per mile).