Recently I snatched some new single-letter domains.
Right now I am in possession of the following four domains:
- e.af (for my own website)
- m.nf (for future nun fungible concept: currently a side product from me is https://mailnonfungible.com)
- y.nf (similar as above)
- v.td (intended to offer to Vinted but got no response lol)
It's not that easy to get those. You can't just go to some website and hit the buy button because there aren't any left. Most likely you would need to get one via an auction, via expired domains (very unlikely), or find some domain investors and buy directly from them.
All those domains I got are from the investors I know. If you are interested in getting one, I might help you in one way or another.