I noticed freezer bags with a vacuum pump while at the grocery store. Made by Glad, I think- a vacuum pump removes the air after the bag is sealed. $8or$9.

I am a little over cautious and have probably over done it a little. I like to keep my seeds in a 1/3 of a dram air tight glass container. I then place this in a small bag and place both of them in a small plastic container packed with loose desiccant. That is next placed in a heavy plastic lock-top style container with large desiccant bags and humidity indicator cards, then finally placed for long term storage in the bottom of a deep freeze. Probably overboard but I at least know they are good and safe for the long haul.

are you serious?

I did say overly cautious didn't I.

How does the desicant dry out the seeds if they're in air tight containers already ?
I put mine in paper postage envelopes, seal them, let the adhesive dry off, then put them in a sealed container with a large dessicant pack I bought just for that purpose from a vegetable seed supplier. This is kept refrigerated for now. For long term storage (5-10 years) I'd freeze them after drying in loose dessicant.

The desiccant removes any moisture remaining in The container after it is sealed and keeps the RH under 5%.

yeah, but if the seeds are "sealed" in their containers the dessicant is not drying them out.

moisture dose migrate over time even into my "sealed" bottles.

In my industry we seal very sensitive devices in bags with desiccants and place these sealed bags into a device called a dry box to avoid the same thing.

do you think that will cause them to last longer?

he's betting the "family jewels" it will, I say NOFUCKINGWAY.
Check this out, anybody who wants to extend the life of they're seeds. http://www.drugs-forum.com/growfaq/1017.htm