Two-Way Radio Ga Ga
Sometimes you're going to have to cue someone from afar, and yelling just doesn't cut it. A bullhorn may work, but if you're anywhere remotely public, your going to call a lot of attention to yourself, and the fact that you don't have a shooting permit. FRS (Family Radio Service) two-way radios are readily available in pairs, with the older two mile versions going for under ten bucks. They have 14 channels to choose from with GMRS (General Mobile Radio Service) models having even more. Just be aware that you need to get an FCC license to use GMRS channels, so pony up or just don't use them.
DVD Player, Zero. External Monitor, One.
I shoot most of my stuff with an older Canon Optura Pi, which has a nice picture (for a one-chip camera) and a nifty progressive scan mode. It can also shoot in 16:9 widescreen, but only has a 4:3 monitor for reference. As a result the picture gets squished, making composition a guessing game. Getting your hands on a portable DVD player with a video input helps a great deal. It not only gives you accurate picture framing, but is always bigger as well (nice to keep cast and crew from looking over the DP's shoulder). I traded a new DVD for mine, which will no longer play discs, but works just dandy as an external monitor. This will keep the cost down, and prevent them from ending up in your local landfill.
You never know where you're going to end up shooting, or where your power source will come from. You may be in an old house with unreliable power outlets, and will need an easy way to test them. Instead of running to every plug with some unwieldy piece of gear, why not this little gizmo that will not only tell you if the outlet is hot, but also six other possible circuit conditions. At only $4 it's a steal, and could save you valuable time and headaches. Cheaper versions that check only for power can be had at any hardware store, but I think a couple extra bucks is worth the added features.
Last week I told you about the benefits of a cheap headlamp found online. Well, the promotional code for that light didn't work, leaving all of you (and me) in the dark. I found another cheap alternative (just over $5, shipping included) from dealextreme that should fit the bill. It doesn't look as elegant as the previous version (it appears bulkier), but will still get the job done and keep your hands free while you fumble around with your script while everyone pesters you about what's happening next.