There's an ETF that tracks about everything. Here is a comprehensive list of ETFs that can be useful for tracking or investing in the performance of certain slices and sectors of the stock market. I will update this list over time as I find new ones, so come back and use this as a reference!

Major Indices

All US Stocks - $VTI (anguard Total Stock Market Index Fund)
This fund employs an indexing investment approach designed to track the performance of the index, which represents approximately 100% of the investable U.S. stock market and includes large-, mid-, small-, and micro-cap stocks. 

S&P 500 - 
  • $SPY (SPDR S&P 500 ETF Trust)
  • $SSO (ProShares Ultra S&P500) - 2X leverage
  • $SPXL (Direxion Daily S&P 500 Bull 3X) 3X daily long leverage
  • $SPXS (Direxion Daily S&P 500 Bear 3X) 3X inverse (short) daily short leverage

By Market Sector

Consumer Discretionary - $XLY (Consumer Discretionary Select Sector SPDR Fund) - a lot of big retail and restaurants

Consumer Staples - $XLP (Consumer Staples Select Sector SPDR Fund)

Communication Services - $XLC (Communication Services Select Sector SPDR Fund) - social media, media, and telecom

Financial - $XLF (Financial Select Sector SPDR Fund)

Energy - $XLE (Energy Select Sector SPDR Fund) - mostly oil

Healthcare - $XLV (Health Care Select Sector SPDR Fund)

Industrials - $XLI (Industrial Select Sector SPDR Fund)

Materials - $XLB (Materials Select Sector SPDR Fund)

Real Estate - $XLRE (Real Estate Select Sector SPDR Fund)
* The meaning of "real estate" brings residential to mind, but this funds actually contains a variety of commercial real estate businesses servicing areas like commercial real estate (Realty Income $O), cell phone towers (Crown Castle $CCI), warehouses (Prologis ($PLD), storage rentals (Public Storage $PSA).

Semiconductors - $SOXX (iShares Semiconductors ETF)

Technology - 
  • $XLK (Technology Select Sector SPDR Fund)
  • $IYW (iShares US Technology ETF)
Utilities - $XLU (Utilities Select Sector SPDR Fund)

By Size

Mid-Cap - $IJH (iShares Core S&P Mid-Cap ETF)

Small Cap Core
  • $IWM (iShares Russell 2000 ETF)
  • $IJR (iShares Core S&P Small Cap ETF)

By Investment Strategy

Value - $IVE (iShares S&P 500 Value ETF)
Growth - 
  • $IVW (iShares S&P 500 Growth ETF)
  • $IWF (iShares Russell 1000 Growth ETF)
Quality - $QUAL (iShares MSCI USA Quality Factor ETF)
Momentum - $MTUM (iShares MSCI USA Momentum Factor ETF)
High Dividend Yield - $VYM (Vanguard High Dividend Yield Index Fund)
Low Volatility - $USMV (iShares MSCI USA Min Vol Factor ETF)

Mid Cap Growth - $IJK (iShares S&P Mid-Cap 400 Growth ETF)
Mid Cap Value - $IJJ iShares S&P Mid-Cap 400 Value ETF)
Small Cap Growth - $IWO (iShares Russel 2000 Growth ETF)
Small Cap Value - $IWN (iShares Russell 2000 Value ETF)

Note that these can be deceptive as they may share some of the same underlying holdings. For example, $MSFT is a top holding in each $IVE, $IVW and $IWF.