In the scheme of things, $8 is nothing
unless money is really tight and the purchase involved is
essential. Electronics gizmos are generally
not essential. Heresy! Say it isn't so! Seriously, in this context "essential" instead refers to paying bills, feeding the family and taking care of their health needs, maintaining a vehicle required to go to work, keeping the electricity on, etc. Millions of people here in the US are struggling to get by and don't have anything by Casio or any other electronic supplier. They can't afford $200+ in the first place for such an item. That should put it in perspective a little. I should also note that if I hadn't received a computer as a gift 18 months ago, I probably would still be using library computers, as getting one simply wasn't a priority compared to taking care of other things. Of course, now that I have this one, I can't live without it...
Critic, listen to the people here who say:
(1) Time is money too.
(2) Being cheap can be the most expensive way of all.
(3) It isn't worth stressing or obsessing over small amounts of money. $8 is small.
I add this: (4) "Post-shopping" usually isn't worth it. This refers to checking prices elsewhere after you've already bought an item. Making this a habit is a good way to get an ulcer or end up on psychotropic meds.
Remember the old joke about how the Grand Canyon was created: "[Insert notorious skinflint's name here] lost a penny in a ditch and began digging to find it."
Above all else, don't become like the people—mainly women, but some men too—who buy something on sale they don't need simply because it
is on sale. "Honey, I saved $1,000 on this $10,000 diamond tiara because it was on sale"—but who needed the tiara? Also, don't become like the people who go to numerous grocery stores on grocery day just to pick up an item here, an item there on sale. Fuel and wear and tear on your vehicle aren't free; neither is your time. As Henry Rollins once sang, "No such thing as free time...All you've got is lifetime" ("Shine").
About time as money: now it's time to bore you to death with a personal application. (Wait! Come back here!) I order copies of technical papers fairly frequently, but these days they are usually new papers, one at a time. Sometimes in the past I was able to look at particular papers by going to Virginia Tech or the Library of Congress, but both are some distance away—especially Tech at 5 hours' drive—so I would wait and compile a list of papers to pursue and kill them all in one trip. Now the supply of papers in the field I'm really interested in (clue: the engine that goes hmmmmmmmmmmm) has dried up, since I've looked at almost all the historical stuff and relatively little new stuff is appearing.
When I do find another paper, even if (say) the Library of Congress does carry it, it's usually worth it to order the paper online from the source or a supplier with a credit card. I might pay $20 for a paper online this way, compared to paying $0.20 per page to photocopy the paper at the Library of Congress. Doesn't sound like a good deal, if you figure that copying a 10-page paper would cost $2 at LoC. But it beats ~$30 in gasoline, ~$5 to park at the Metro station in northern Virginia, and ~$5 for Metro fare just to
get to LoC to pay that $0.20 per page.
And then there's Mr. K's wear and tear from getting up at an indecent hour to beat a
little of the traffic and driving 3 hours one way to northern Virginia; in truth, I don't like spending long periods of time behind the wheel as I once did, especially with the stop-and-go traffic in so many areas today. I ain't as young as I used to be. Once recently, on a
Saturday, traffic was stop-and-go from northern Va. all the way to Richmond, a distance of nearly 100 miles. Usually the weekdays had the worst traffic. Not anymore! Let's say I value my time at $20 an hour. I'll "spend" some $120 in time for the DC round trip. Or more if traffic is bad, as it increasingly is.
Suddenly, "saving" $20 compared to paying 20 cents a page isn't such a bargain when you add all the expenses and the
time. I also generally don't have the free time to drive somewhere distant because of my responsibilities at home now, so ordering online it is.
Even if I examine a paper and decide it isn't relevant to my needs and don't copy it, which happens a lot, I'm
still out the time and money to get to Blacksburg or DC, so even here online purchasing is often better. (For several papers or other sources to view at once it remains a different story. Also, a paper unavailable elsewhere but Tech or LoC would change the situation, if I wanted that paper badly enough.)
It's all about time management, and that's as important as $ management.
Now, what was that about $8? Trust me, you'll drop $8 just to buy a meal at McDonald's or any other poison chain these days.
Don't obsess about it! 
