A Couple Odd Stamps

Hello, I'm currently going through a small collection trying to figure out what's what. At this point, I'm just posting random pictures of things that catch my eye with the hope of learning more about them. Eventually, everything will be available for sale. Here's a couple oddballs in fancy cases.

The top two pairs of stamps (James Hoban) are Scott #1935. This stamp was issued immediately before a postal rate increase. As a result, it was also issued as a 20-cent stamp (Scott #1936). Both stamps were issued late in 1981.
The bottom stamps are computer-vended postage issued in 1992. The 1-cent stamp is either CVP31 (dull gum) or CVP31a (shiny gum). The stamps without a printed denomination would also be of the CVP31 type, but without a printed denomination there's no way to determine the font type (I or II). I do not know whether these are considered errors. Perhaps someone else can enlighten us on this topic. In any event, I could not find any such listed in Scott.
Neither 1935 nor CVP31/31a are very valuable. Catalog value for mint 1935/1936 is 35-cents. For CVP31/31a, the catalog value is listed at 75-cents but a footnote implies that the 1-cent denomination was common & is worth only 25-cents. Like most modern postage, they really are worth little more than face value.

Thanks that info, JLLebbert!

My thought, the .01 stamp was placed in this arrangement to demonstrate what the blank stamps are supposed to look like.

As for the 1-eyed and 2-eyed Hobans, I assume the lack of a distinction between the two means there no difference in value, etc.?

I now understand why you posted these stamps.
I didn't even notice the apparent difference in the eyes. There is no mention of a 2nd variety of this stamp in either Scott or Datz (error catalog), so I'm guessing this is not considered an important difference. The Scott catalog pictures the stamp on the left, while both Harris & Durland appear to show the one on the right ... and all of my copies (18 & 20 cent) are like the ones on the right. Maybe someone else is aware of what appears to be a difference in the eyes on the Hoban issue & will chime in. Thanks for bringing this to my attention. If nothing else, it is an interesting anomaly.
Added: A quick look on ebay seems to find only the 1-eyed version, although I didn't take a close look at very many. I think the apparent 2-eyed version might be caused by a slight mis-registration of colors on that stamp.

Thanks JLLebbert. Appreciate the input!

JessEm....According to SCOTT....the 1c has minimum value.
A purchaser could change the value for .01 to $99.99 per stamp.
It seemed that collectors and dealers made 1c values between all
the plate #s and made those the 29c rate (current of the day).
Which was later changed to 19c minimum.
On the non-demon stamps....once a short supply was printed the buyer
would then pull on the stamps being dispensed from the machine and
cause the value to not be printed. Thus the missing value.

Ok. This is all very educational. From what I gather, the blank stamps are not particularly common, but they're not particularly valuable, either.

minor color misregistration on the 2 eye vs 1 eye

the blanks could indeed be created by pushing on the output to keep the same stamp under the print head while the machine tried to feed the next stamp to the print head, and then they yanked on the output quickly and it would pull out the slack and you'd get one or more blanks

Also, some one got a roll or partial roll of blanks from a friendly postal worker

So, not super common, but not that uncommon, but still worth more than a buck