I did a post about this a few days ago but this chart is way better (from Gregor Macdonald via Stockcharts.com). It shows how the value of the S&P 500 since 2000 is down 70% priced in the Reuters-CRB Continuous Commodities Index (CCI). Since the March 2009 low the market has only increased in "nominal" terms not "real" terms (adjusted for commodity inflation). Look how S&P:Commodities ($SPX:$CCI) vs. S&P are diverging. A lower Dollar is pushing up the S&P. However, a lower US Dollar, QE liquidity and global supply constraints are pushing up commodities more than the S&P. $SPX:$CCI is trending towards the March 2009 low (top chart) while $SPX pierced through the April high (bottom chart). It is interesting and people should know about this since higher commodity prices could increase food and energy costs. Fed Governor Kevin Warsh is monitoring this.
Side note: The S&P is at the 61.8% Fibonacci retracement level again