> The hard part of almost any space-based power consumption is the difficulty of later dissipating the wasted heat energy. ... Without lots of clever technology

> The hard part of almost any space-based power consumption is the difficulty of later dissipating the wasted heat energy. ... Without lots of clever technology, then, your space-based laser is a double-edged sword. Not if you design it like a mine or a one-shot munition. Cheap high-powered lasers and targeting systems will pave the way for laser-mines in space. Without air, there is little need to pulse your lasers. Your weapon might as well expend itself ASAP to do maximum damage without prolonged tracking and risk of retaliatory fire. If you can only sustain pulsed fire at say 6 shots per minute, that gives your enemy a lot of time to triangulate and return fire, potentially with more lasers than you have. However, you could simply expend your munition by firing it continuously for a minute until your mine overheats and its systems fail. If you're lucky your mine might survive the battle through a bad retaliatory shot, or by destroying the target. If your mine survives, it could well live to fight another day. It will eventually cool down, and assuming you'd provide it with solar panels it could well charge itself up to repeat the process next time you're attacked. It's also nice to point out that smaller objects dissipate their heat faster, so attaching your weapons inside your ship may only serve to hamper your efforts to fight effectively. If you're actually defending something, like say a asteroid mine then you're likely to have enough spare material to afford heat sinks, or you could use several meter wide asteroids to mount your lasers. Drill tubes and heat-sink into the asteroid (it doesn't matter what it's made of, but a metallic asteroid would be ideal) with copper-rods and you could fire for even longer periods. On top of this, you could use the asteroid as a heat-sink for the enemy fire. If you know a ship-mounted laser only fires once every 10 seconds, you could simply realign so that there's a high probability that your enemy will be hitting rock and not a vital system. I doubt we'll be using them any time soon, but I think what people fail to understand is the incredible vastness of space, but also the potentially endless resources we will find there (at least from our present perspective where we can't strip-mine our planet because of all that inconvenient molten-gooiness that is containing precious materials).