exactly, there's a reason there are $1000+ arri lights, they're better, but that doesn't mean you NEED those. Start with the worklight until you need/can afford the "good" ones, they'll do you fine
There are a lot of cool things you can do with the little worklights. I've made some "disposable" production tools using worklights and my brake with some .063 aluminum, but there are easier ways to do it. I'd post a pic for you but I gave these lights away already. Maybe I'll make more.
For a 500w or so get yourself a baking pan that you can attach to the front and then drill out a bunch of ameoba type shapes... or whatever kind of various size holes you want to do... like from 1/8" all the way up to about 3/4"... There's your cookie shooter. You can rivet, screw, or otherwise attach some tabs to that thing so that you can gel it while allowing some air circulation.
For a 125/250w switchable you can cover the face with a piece of aluminum and then attach an aluminum tube (square or round, doesn't matter) to the middle of it... so that you can see all the way to the bulb through that tube. There's your hair/rim light.
If the bulbs are protected anyway I'd lose the protective glass... by protected I mean as per my above description.
Basically all you're doing is making your own tota's with gel frames... nothing wrong with that.
You can also find older fresnels on ebay which aren't that expensive. There's no need to pay $1000 for a light in any case. You can also add barn doors to them to by one of several ways. Here's a quick video tutorial I put in my Cool Lights Video Magazine a while back ("Attaching Barndoors to a Worklight"):
There's no reason to be ashamed of using these--they are a floodlight and a floodlight has a valid place in your kit. The worklight kind of flood is a "stop" we all make along the way in the progression of equipment we buy over the years. It allows you to wade into video making without spending a bunch of money and then as you get more sure you're going to stay you can start spending more on equipment and tools.
I'd be careful of taking the glass off though unless there will be other protection. Some quartz halogens emit UV and the glass is there to protect against that.
Extension cord, generator, or DC/AC converter and battery isolator.
You can guess how much power a couple 500w lights use. That's too much juice for anything other then what I listed above.
If you want portable and AC independent then you gotta' look into flos... then get yourself a smaller DC/AC converter and you'll have to limit your lighting needs to a few hundred watts.*
*This is a general assessment based on the nature of the above post and the assumption that said post was cast from a standpoint of budget and experience limitations. I realize that in the professional world that there are more complex and expensive possibilities in handling needs such as portable power and power regulation to higher wattage lighting arrays. Please note that the title of this thread is "$20 Home Depot Lights" and that I'm basing my reply on that line of logic.
Thanks for the barn door video. Just solved my problem with attaching doors to my scoop light. Also, I've been using the daylight flo bulbs (the ones you buy from home depot) now in the scoops. The color is very pleasing and I find it easier to gel these to the color I want instead of trying to gel a tungsten balanced flo bulb. I did some test and even though the flo bulbs say they are tungsten balanced I always see much more of a pink hue in the color. Doesn't quite look like tungsten. Actually it looks very sickly. Another reason why I like using the flo bulbs are because of the heat factor. More and more I'm getting sick of running so many hot lights around set. I also LOVE the 4 foot flo worklights you can get at home depot. I use them all the time. I highly recommend. I've gone off the subject now. Yes, I think the halogen worklight is worth it if you're lighting large outdoor areas. But not actors in a room. It's a bit uncomfortable. Test them out on yourself and see if you find it to your liking.
Sorry to double post but since we're on the topic of generators. I found a little mini portable battery jump starter system that has a built in power outlet. I did a test and was able to run a 100 watt bulb off it for 1hr and 1/2. Might not seem like much but if you need to light up your actors outdoors at night on a remote location or on a street, you could power a few flo bulbs for quite a while to get the shots you need. It's a cheap alternative. You can't do nothing too fancy with it but it helps. The system cost me around 85.00 at Home Depot. And it's rechargeable and very quiet, just has a fan noise. Man, what Home Depot has done for the independent filmmaker. Do they even know.
I'm not sure if you're familiar with the Harbor Freight Router Speed Controls... but if not, these make excellent high-power dimmers. This is another product that is secretly common knowledge on the boards... meaning if you hang around long enough you'll realize that just about all of us bought 2 or 3 of them (or more) since you can dim up to a 1500w light with one... and they're between $10 and $13 depending on the current sale at Harbor Freight.
Check the price of a 1500w dimmer from filmtools or some other source... it'll be about 10x that price.
The ability to dim your Home Depot lights and dial in the intensity is a pretty big step in the control department... and you can use those same "dimmers" once you upgrade to Arri fresnels or anything else tungsten.