In my opinion, things that required continuously payments to or worth.

1. Employe can pay employees regular basis.
2. If the Exchange (use it, frequent trading can be done using LN).
3. Buying Coffe, Books etc

I hope LN will become mainstream as early as possible.

Did you guys tried the how quick is this

Try it now - Use this wallet  - https://htlc.me
and Pay to  - http://yalls.org