Not since Bill Harris' four-game run with the 1931 Pittsburgh Pirates has a National League pitcher started three-plus games and kept his ERA under 1.00. This year, three hurlers in the senior circuit are off to that kind of start: Rich Hill, Tim Hudson and Brad Penny.
Chicago Cubs' pitcher Rich Hill (3-0) has the lowest ERA through at least three games started (0.41, 22 Innings Pitched) since Earl "Crossfire" Moore managed to avoid giving up any earned runs while pitching for the Philadelphia Phillies back in 1908. Moore accomplished his feat in 26 innings. Those would be the only innings he would pitch that year. Given their history with pitchers (*cough* Prior *cough* Woods *cough*) I think I just made some Cubs fans very nervous.
Atlana's Tim Hudson (0.62, 21 IP) and the Dodgers' Brad Penny (0.89, 20-1/3 IP) are both among the top 10 lowest ERAs through three-plus starts as well.
And just so you American League folks don't feel left out, your most recent starter to pull off a sub-1.00 ERA through three or more starts was Bob Milacki (0.72), who did it in 25 innings with the 1988 Orioles. The only other AL pitcher in the top 10 is Bruce Howard (0.81) of the '64 White Sox.
The longest such streak in the majors is 6 games and two pitchers, both of them Pirates, hold it. Nick Maddox held his ERA to 0.83 in 54 innings in 1907. Interestingly, Earl Hamilton's numbers are exactly the same (0.83, 54 IP) in his 1918 campaign.