DER (Defensive Efficiency Ratio) : “measures the percentage of times balls in play are turned into outs by the team’s fielders, not including homeruns. There are different versions of the formula for DER but one most commonly used is (BFP-H-K-BB-HBP-0.6*E)/(BFP-HR-K-BB-HBP) where BFP = batters faced pitcher, H=hits allowed, K=strikeouts, BB=walks allowed, HBP=hits batsmen and E=errors”
DIPS: “The Defense Independent Pitching Statistic (DIPS) system was invented by Voros McCracken. His studies of pitching statistics suggest that major league pitchers do not differ greatly on their ability to prevent hits on balls in play. The rate at which a pitcher allows hits on balls in play has more to do with defense and luck than to his own skill, and can vary greatly from year to year.” The pitchers contribution to overall team defense consists of walks allowed, strikeouts, homeruns allowed and hits batsmen issued. 
BABIP (Batting Averge Balls in Play) : This is a measure of the number of batted balls that safely fall in for a hit (not including home runs).[more] [BP]
FIP ERA (Fielding Independent Pitching ERA) : Earned Run Average was supposed to remove the effect of fielding errors from runs allowed. However, there is a human factor involved where a hit or an error is dependent on the the official scorers interpretation. Moreover, it does not take into account the ability of fielders to get to balls. FIP ERA measures pitcher performance essentially independent from fielding. The formula is HR*13+(BB+HBP)*3-K*2)/IP plus a league specific factor to make it equivalent to ERA. THT Stats
UZR: (Ultimate Zone Rating ) is the most effective and comprehensive measurement of a player’s defensive ability. The statistic judges what the chances are that a ball in play will be able to be converted into an out depending on how hard the ball was hit, what zone it was hit to and whether it is a ground ball, fly ball or line drive. That probability is then adjust to take into account the park the ball was hit in, how many and where people were on base, the handedness of the batter, the pitcher’s groundball-to-flyball ration and how many outs there were at the time [UZR]
PMR : Pinto uses play-by-play data to determine the probability of a ball in play being converted to an out based on six parameters: Direction of hit (a vector), The type of hit (Fly, ground, line drive, bunt), How hard the ball was hit (slow, medium, hard), The park, The handedness of the pitcher, The handedness of the batter.[link]- 2006
ZR: John Dewan’s Zone Rating . ZR basically is the proportion of balls hit into a fielder’s zone that he successfully converted into an out. A fielders “zone” is considered to be the areas on a ball field in which at least 50% of batted balls are handled for outs. Zones are standardized and defined separately for each position. The revised version of ZR lists balls handled out of the zone separately and doesn’t include them in the calculation, and also doesn’t give players extra credit for double plays.
Arms in Outfield: five different situations when an outfielder’s throwing ability comes into play: Single with runner on first base (second base unoccupied), Double with runner on first base, Single with runner on second base, Fly out with runner on third base, fewer than two outs, Fly out with runner on second base, fewer than two outs (third base unoccupied).
PECOTA : (Player Empirical Comparison and Optimization Test Algorithm which boils down to the last name of Bill Pecota, a former major league utilityman) PECOTA accounts for these sorts of factors by creating not a single forecast point, as other systems do, but rather a range of possible outcomes that the player could expect to achieve at different levels of probability. Pecota uses as many as 100 comparables in generating its forecasts.
VORP : is a sabermetric analysis developed by Keith Woolner that seeks to measure the contribution, in runs, of a player beyond what a backup (or replacement-level) player would produce for an average team given the same amount of playing time. VORP is adjusted for park and league, and position (for non-pitchers)  BP
ZiPS forecasts: fangraphs
Chone forecasts: fangraphs
Marcel forecasts: fangraphs
BigDawg an online fantasy magazine with projections
Heater Magazine online magazine
Win Shares: The idea was to develop a statistic that allows you to compare shortstops and outfielders, starters and relievers, relievers and shortstops, etc. Since the win is the ultimate measure of success, James developed a stat that measures each player’s contribution to his team’s wins, or Win Shares-AL NL —THT Data
RC : “Runs Created is a stat that was created by Bill James. To put it simply, it is how many runs a player has created for his team” —THT Data
prOPS :Predicted OPS. looks as types of batted balls (line drives, flyballs, etc.) players were hitting. Is there a correlation between these variables and hitting success? If so, maybe we can learn something about how “good” players are actually playing by looking at this data. Uses Line drives per batted ball, Groundball-to-flyball ratio, Walk rate, Hit-by-pitch rate, Strikeout rate, Home run rate, Home park of the player. under over
WPA: “difference between the Win Probability when a reliever enters and when he leaves a game, if his team’s offense scored at an average rate. It’s a measure of how well he pitched and how critical his innings were. Tie games matter a lot. And you don’t have to finish a game to receive WPA points.”
WXRL:a way to assess past performance, usage, and game importance. Hoffman 5.995, Linebrink 3.995