Stumbled across these very cool and useful devices via Amazon: http://www.esitest.com/fuse_buddy.html
For the causal DIY mechanic the integrated versions (#302M & 304B) would be useful for loads not exceeding 20 amps. They are fuse protected just in case one exceeds that current flow, most helpful checking for parasitic draws as well as power consumption while a device is in use.
Those using DMM's would find the adapter versions (301M &303B) very helpful for the same functions although they are higher amp draw rated than most DMM's which are 10 amp max without other adapters.
Loads up to 30 amps could use model's 305M or 306B: http://www.esitest.com/305_306.html
This same company offers current loops used in conjunction with "clamp meters" that will measure DC flow: http://www.esitest.com/307-308.html
Nice tools for those involved with electrical work or trouble diagnosis.