FEAC
Fidelity Enhanced U.S. All-Cap Equity ETF
stock NYSE ETF

Not sure these are really under the radar if you look at AUM, but they don't get mentioned much in this space:
FNDX and DFLV for value. FESM for small cap. AVLC and BKLC for large cap (alternatives to VOO, but not S&P -- BKLC is a great fund with a 0% expense ratio! More people should know about it). DFUS for US total market (also have my eye on FNDB and FEAC in that space).
SPGM for global (alternative to VT).
DFAX, FIVA, FNDF, and IVLU for international.

Not sure these are really under the radar if you look at AUM, but they don't get mentioned much in this space:
FNDX and DFLV for value. FESM for small cap. AVLC and BKLC for large cap (alternatives to VOO, but not S&P -- BKLC is a great fund with a 0% expense ratio! More people should know about it). DFUS for US total market (also have my eye on FNDB and FEAC in that space).
SPGM for global (alternative to VT).
DFAX, FIVA, FNDF, and IVLU for international.