I love mempool.space's block explorer and there are a few other ones that have come out in more recent years that are cool, too. But I like the idea of a block explorer that is kind of ephemeral like this:

First I made node_faker, which pretends to be a bitcoin node by emulating bitcoind's api, but getting the data from electrum servers. Then I tried various apps against it, among which were LND -- which worked, albeit slowly -- and btc-rpc-explorer -- which did not work.