Ask HN: What are some interesting projects to reuse your old devices?

Many older laptop batteries are simply a set of 18650 batteries wired together. I've "fixed" about 30-40 batteries. (1) Carefully take the battery pack apart, (2) Visually inspect the cells for any that are bulging or just, otherwise, look wrong -- take these to the electronic recycler, (3) charge each cell in an 18650 charger (mine is a Micro USB unit that charges very slowly), (4) test in a multi-meter, toss any that are bad, (5) put them in a low-drain device for a few hours[0] and throw out any that under-perform.

In a typical "failed battery" there's rarely more than one dead cell in my experience. And I've had packs with as many as 9 cells.

From there, it's a matter of putting it all back together. There's soldering involved, and you have to be extremely careful -- hit the battery with the temp required to melt the solder for too long and you have a seriously dangerous situation on your hands. I use two 3D printed clips and alligator clamps to hold the wire, wand and battery at distance from one another, battery on the bottom, wand on the top, wire in-between, and a 120mm fan, requiring me to only hold the cable to the wand and the length of solder.

Can't caution enough that it's exceedingly dangerous soldering this kind of battery. I originally built the rig because I wanted to improve the quality of my soldering -- I'm pretty terrible with an iron, but I made several changes after I had a small number of batteries start failing after repair and a few searches led me to believe I may have damaged them[1] with my poor soldering skills. My rig involves two 3D printed clips, one to hold the iron exactly where I want it, and one to secure the battery. The cable to the iron has a length of wax lace on it to let me pull it back up/remove the iron from the rig with a yank at a distance.

I use an alligator clip to hold the wiring in place and a long length of solder so that I can stand an arms length away. The iron "drops" in -- it's mounted on top, battery on bottom, wire in-between -- so I can heat it up an inch or so from the battery, I place tip of the length of solder in its spot and "tap" the wire of the iron to drop it into place. When I see it melt the tip of the length of solder and the small amount that's on the wire, I pull up on the string to move the iron away, wait a few seconds so the 120mm fan can cool things a little, and put a new battery in.

Goggles, gloves and a nearby fire extinguisher of the right kind are a really good idea. I also do the work in a large, mostly empty, shed with doors that, when opened, eliminate nearly an entire wall and work directly on the cement floor.

A lot of devices use 18650s and not all 18650s are the same. The one powering your drill might be able to handle higher drain than the one that came out of your laptop; don't mix those up. I was given a cardboard box full of dead laptop battery packs from the same model, so I was taking cells from a similar source each time.

[0] I use an adapter that lets me power a Raspberry Pi via an 18650.

[1] And likely made them into a fire hazard on their own.

Have you noticed any issues? Especially transcoding?

There are no Core2 desktops without GPU consuming 200W when idle. Even at full load you will be hard pressed to peak over 150W.

From my (limited) experience RDP is significantly better than VNC in terms of sluggishness and glitches. The second thing is that both VNC and RDP will try to transmit those parts of the screen that changed since the last frame rather than simply sending full "screenshots" for every frame. As a result the final effect highly depends on what are you using the remote desktop for.

Since my work is mainly coding in IDE and working with several ssh sessions, I almost exclusively work with text which is much easier for a great remote desktop experience. On the other hand, when I tried watching videos over remote desktop it was really bad.

The other things that you might consider is UDP vs. TCP, especially since some routers can handle long UDP connections badly. Since you are using VPN tunneling, you should probably avoid TCP over TCP scenario: if the VPN connection is using TCP, then I would rather use UDP for remote desktop connection. I would aim for UDP over UDP, but in a situation where the router can't handle UDP properly you could try TCP over UDP (that is VPN: TCP, VNC: UDP). You could also try to tune mtu size in tincvpn config.

2004 1.5GHz Centrino isn't exactly fun to use, but it's my OpenBSD playground. Need to update, but with 6.2 I could browse 1 concurrent website in a current browser.