Gasolin

It doesn't work that way.

The FDIC insurance is $250k by type of account per depositor, so you can try to have a single account, joint accounts, etc etc at your name up to $250k. And some trusts, revocable or not (where the insurance amount is then more determined by the number of beneficiaries).
But again, just creating across multiple institutions won't work, even if your institution doesn't know, the FDIC basically requires the deposit insurance amounts to be calculated per institution per account type per depositor and sent to them regularly.
So they are going to know if your aggregated number is above $250k or not.

Anyway none of this makes sense, so you should not worry.
In case there is a real problem with an institution, if this institution is too big, the FDIC ultimate plan is normally to setup a substitute bank and transfer the deposits into that account instead of paying back "per se".
Because don't be fooled, there is no way we are able to pay $250k per depositor per type of account for everyone, that's an illusion.
Other countries often limit to $100k per depositor accros all type of accounts or so and even them are not certain they can pay back people in case of a real crisis.

Apologies for derailing the thread btw.