The briefcase is a conference bag I got years ago. It has some pockets on the outside and a main pouch closed with a zipper. I took a keyring and put it through the zipper, then soldered it closed. Then I took a 4-letter padlock and attached it to the keyring and the strap so it couldn't be opened. On the outside of the main pouch in the other pockets were a variety of pens and cards and junk, but the most important part was the journal. Inside the journal were a few word scrambles, the solution to which were a set of four letters, which were unscrambled into the word GOAT, which was the password. See the file in this project for the journal pages pdf. Once they opened the pouch, inside were a bunch more things; a Digikey ruler (red herring) a melted santa candle (creepy red herring), some pens and pencils, 3 network patch cables (required for defusing the bomb), and a series of folders. Each folder had some blank pages inside for filler, but also a sheet that had a blueprint of a potential christmas-themed weapon of mass destruction. On each of those blueprints (see the PDF), was a picture of a bomb, but only one of them matched the actual bomb. That picture showed the proper arrangement of network cables to defuse the bomb.
There wasn't anything electronic or difficult about this particular puzzle; but it was a necessary stepping stone to get from entrance into the lair to instructions for solving the bomb puzzle. There was a timer on the bomb that was making noise, and the countdown was triggered by moving the bag, so there was a lot of stress to solve the two puzzles within this briefcase before the bomb timer went off. There were a lot of red herrings that confused people, which added to the amount of time it took to solve; overall it took roughly 15-20 minutes for people to get through this section.