Links
t-test calculator:
http://www.graphpad.com/quickcalcs/ttest1.cfm
Student's t test (Keith Bower):
http://www.youtube.com/watch?v=snrajeiZLK0
Paired t test (Keith Bower):
http://www.youtube.com/watch?v=OyxBLgtLB-U
Variance reduction for simulation practitioners (Barry L. Nelson, WSC, 1987):