To be able to identify poison ivy, seeing one picture isn't going to do it. you gotta' see a lot of poison ivy, in all its many leaf shapes and sizes. if you spend time outside, browse these pictures! most pictures have descriptions with editorial notes. to read my lengthy identification guide go to http://electricant.net/poisonivy
'leaves of three, let it be' is a load of crap. if you plan on avoiding every three-leaf cluster in the forest then you've got your work cut out for you. find here some common three leaved plants which are NOT poison ivy. most pics have comments on distinguishing characteristics
Jewelweed, along with plantain (the north american weed, that is), is one of a few highly regarded folk remedies for poison ivy, both preventatively and symptomatically. I have no experience with jewelweed myself, but thought i'd toss a few photos up for identification.
This is useful to see the progression of a bad poison ivy reaction. unscientific synopsis:
1. you can not 'cure' poison ivy, only make it itch less, despite claims.
2. hydrocortisone, calamine, and witch hazel are still cheap and still work. a little.
3. 'zanfel' isn't worth forty bucks.