I have extra security clearance being a pilot. I can take a full coffee, water bottle, etc through security. They swabb the bottom, look in the mug, send me on my way. I have gotten crap for that. We can travel with regular size shampoo, shaving cream etc. Friends have gotten crap for that. Others have gotten crap over razors. Even with the extra wiggle room in these regards I would sure as heck not take a knife with me. That being said I am also Scottish so... ya know I don't wanna lose $25! It is so dependent on the TSA/CATSA person. As already mentioned, tactical style pens are being taken more frequently. On the flip side, you can get awesome deals on all the stuff that gets confiscated once a month at the YYC chapel when they sell all that for fundraising!