Given the background description of some cooking related query, summarize the question into a title

I sometimes find myself wanting to eat whole nuts in situations where I have no access to a nutcracker, whether because I'm at work or traveling or otherwise not in a place where I might be expected to keep a nutcracker on hand. I've had good luck squeezing two pecans together in my hand, but what other nuts are good for improvised cracking methods?
Which nuts can be cracked without tools?