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Absolutely!

Suppose I'm editing a text file, and I'm working through a tradeoff between data volume and accuracy, where more accuracy requires more data. I have an array of 14 sensors, and I can configure them to take either 100-byte samples or 500-byte samples, and I can take samples at intervals between 1 and 60 seconds.

So I make myself a little table:

    sensors size interval
    14      100  1
    14      100  30
    14      100  60

Then I duplicate it:

    sensors size interval
    14      100  1
    14      100  30
    14      100  60
    14      100  1
    14      100  30
    14      100  60

I'm using kakoune, so I can put my cursor on the 100 in the first duplicate row, press C twice, then press r5, and now I have this table:

    sensors size interval
    14      100  1
    14      100  30
    14      100  60
    14      500  1
    14      500  30
    14      500  60

Now, I want to know bytes per day, and this is where the math comes in. I start adding columns. First I duplicate the three existing columns, since I want to see them next to the result. I can do this by putting a cursor at the beginning of each row, highlighting the whole thing, and pasting. I also hit & to line up the pasted selections.

    sensors size interval
    14      100  1        14      100  1       
    14      100  30       14      100  30      
    14      100  60       14      100  60      
    14      500  1        14      500  1       
    14      500  30       14      500  30      
    14      500  60       14      500  60

Now, because I don't want to have to think about the stack too hard, I put 1440 (minutes per day) and 60 (seconds per minute) in before the interval column.

    sensors size interval
    14      100  1        14      100  1440 60 1       
    14      100  30       14      100  1440 60 30      
    14      100  60       14      100  1440 60 60      
    14      500  1        14      500  1440 60 1       
    14      500  30       14      500  1440 60 30      
    14      500  60       14      500  1440 60 60

Then I add my operations. And keep in mind I'm still using multiple cursors, so all this stuff is just getting typed one time.

    sensors size interval
    14      100  1        14      100  * 1440 * 60 * 1 / p      
    14      100  30       14      100  * 1440 * 60 * 30 / p     
    14      100  60       14      100  * 1440 * 60 * 60 / p     
    14      500  1        14      500  * 1440 * 60 * 1 / p      
    14      500  30       14      500  * 1440 * 60 * 30 / p     
    14      500  60       14      500  * 1440 * 60 * 60 / p

Now each line has a little dc program on it, like 14 500 * 1440 * 60 * 60 / p.

I then highlight the back half of each row (again, still working with the same set of cursors the whole time, it takes way longer to explain this than it does to actually do it.) I type

    | dc

and each of my selections gets run through dc. The result is:

    sensors size interval
    14      100  1        120960000
    14      100  30       4032000
    14      100  60       2016000
    14      500  1        604800000
    14      500  30       20160000
    14      500  60       10080000

That's not super readable, so I cursor over three times (multiselection is still active!) and insert commas, and then I do it again:

    sensors size interval
    14      100  1        120,960,000
    14      100  30       4,032,000
    14      100  60       2,016,000
    14      500  1        604,800,000
    14      500  30       20,160,000
    14      500  60       10,080,000

The result is I've done a quick back-of-the-envelope calculation on how much data I need to handle in each scenario.