Made from 1888 to the early 1930's, the Stanley Odd Jobs #1 was one of the few tools that old time craftsmen needed to build anything.
It's an inside miter and try square, a depth gauge, a scribing tool for arcs and circles, a T-square, a depth marking scribe which is excellent for marking out mortises, a plumb level and a rule!
In recent years the original Odd Jobs has been copied in the far east, and is available from every DIY woodworking store and tool catalog. Beware of the poor copy which is being sold at Harbor Freight, and which is being sold on eBay using deceptive descriptions. When in doubt ask the seller the brand name. If they don't know, or if it's CEN-TECH, take a pass.
An original Stanley Odd Jobs #1 will run you $25-75, depending on the condition and if is comes with the proper rule or not. The decent clones run around $35 with a 6" 0r 12" brass-edged rule.
Click link to find the Odd Jobs #1 for sale on eBay