I divide maintenance into two categories:
The first category is maintenance that needs to be done immediately, for example changing a burned out light bulb or emptying a full shop vac.
The second category is preventative maintenance,in that group I include sharpening, emptying the dust collector system,changing mitre saw blades, cleaning and waxing machine tops sorting out plans, templates, books and receipts.
To address the second thing first:
I try to keep the dust collection system from getting completely full because it is a bit of a production to empty the big bag and re-attach it to the dust collector. I have found that if I put a large garbage bag or a paper leaf bag inside the lower bag of the dust collector it smooths the process. I end up making less mess because I am not dumping the lower bag out at any point. The paper bag also holds the bottom bag up while I re-attach it to the unit.
Last evening I took some time and set up my sharpening station, a Worksharp, an assortment of stones and some Scary Sharp granite slabs with wet sand paper on them. I had a couple of chisels that really needed work but I also checked out the everyday shop chisels and knives to make sure they were in top shape. I take an evening every couple of months to do this and so I always have sharp tools at hand when I am working. Eliminating the interruption of having to sharpen something while working is worth the maintenance time spent. I keep a strop available for honing all the time and I just don't like to have to stop what I am doing to sharpen a chisel or plane.
Waxing machine tops is a job that gets done when I take time for a serious sweep and vacuum. About once a month I go crazy on the shop, I sweep in all the corners, crawl under the benches and tools and really clean the place up. This is the job that I would happily give away to anyone, but like so many of the unglamorous jobs, it needs to be done. Since I don't have a separate space for finishing, I need to try and keep the general dust level under control or every time the furnace runs the shop fills with a fine layer of wood dust. After I get all the sweeping and vacuuming done I check out the tops on my table saw, band saws, jointer, and router table. I make sure that the tops haven't attached any glue drops of bits of pitch and then put a light coat of paste wax on the metal tops.
I've found that my table saw and mitre saw blades need to be sharpened about twice a year and so I put the spare blades on and drop the other blades off to be sharpened, that is a job that is due soon.
I the worst part of preventative maintenance is paper. To keep from losing my mind at tax time I try to gather up and organize the various invoices and receipts that I collect over the course of the year. Nothing is worse that knowing you've got a big write off for which you can not find the paper work.
And for excitement recently I was given a dozen or so really cool plans for scroll saw and wood carving projects. They need to be labelled, carefully folded and filed in the appropriate folders. If patterns and plans are not dealt with correctly there is no chance of ever finding them later when you want them. I know this from sad and bitter experience.
Since any time in the shop is 'good' time even maintenance time is good time, just not as good as building time. The hidden bonus is most of the shop cleaning time can be spend accompanied by a beer (except sharpening) which eases the pain somewhat.