Well, I finally got around to ordering a UPS for the server and the DSL modem. Hopefully this means that it won't end up going offline or crashing the next time there's a lightning-related brownout or outage.
And now for some shameless promotion of a specific manufacturer, I have of course decided to spend a few extra bucks on what should be a quality UPS from a manufacturer known to make quality hardware, APC. I suppose I could've done what most people would've done and bought a slightly cheaper model from some other manufacturer but in my experience in the long run it pays to go with quality hardware instead of trying to save a few bucks in the short run..
Of course, whether this was a good choice or not is something I'll have to get back to you on in a few days when I've received and installed the unit. From what I can tell it should be a pretty straightforward process but as always there are bound to be stupid little problems (like that I may have commented out the necessary USB drivers from my kernel config).