Best logbook for the CFI is the ASA SP-6...plenty of empty columns that you can fill in with whatever you want. I leave mine at home and put totals into the calendar on my phone (1.2, N12345, 1 landing, .7 night, etc.).

How much for a cheap fire/waterproof safe guys?

Can't believe nobody has mentioned www.flightlogg.in. It's free, maps all of your flights for you on google earth (pretty cool), can calculate any totals you want, does your 8710 for you, shows all your currency information, oh and did I mention it's free? I get a backup spreadsheet of all my entries emailed to me after each update so that if the site goes south I have all my information electronically.