Not much happened today. The snow precludes caching.
I bumped into the limitations of the Raspberry Pi today, twice. Once was in moving a forum that uses Yabb from the server it was on, to a Pi. Immediately, it was running like treacle. Yabb is a notorious resource hog. It doesn't use a database, it keeps everything in directories of tens of thousands of little files - not a great idea. After going to the trouble of setting it up, I had to move it back.
The other failure was a database server; again I tried moving it from a conventional computer to a Pi. Again, it ran very very slowly, and here, I think, the problem is that I'm using an encrypted file system, which means that every time I copy a file, it has to go through the encryption process, which uses a lot of CPU. For the data storage device, I used a 2 1/2 inch IDE drive (an old IBM one) and those aren't very quick either. So again, I had to scrap the idea, and go back to the ordinary computer.
Next, I had a look at one of the APC Smart-UPSes like the one I successfully re-batteried. This one still had the old batteries in, and I've learned something. If a UPS needs new batteries, take out the old ones as soon as possible. If you leave them in place, they swell up and you have to use a hammer and crowbar to get them out. I got them out eventually, and I now have a pile of scrap lead for sale.
I'm still dead keen on the Pi - so much so that I went to RS-Online again today and ordered six more. I don't actually know what I'll use them for. Yet.