Do these things have any value in todays collecting world? I have a couple left over from my Cartridge collecting days.

Depends on which ones they are. Any of them have a value but some are more rare/desireable .

Iconoclast would be the guy in the know on current values - I would only be guessing . But dont give them away , you might be surprised.

Despite Mr. muzza' uncharacteristically kind comment, I'm no expert on the details of the gyrojet loadings. However, these are worth a minimum of $20 each if even the most common loadings and could well be worth substantially more "depending."