[R] simulate binary data from a logistic regression model

[Michele Grassi]

Hi.
How can i simulate a binary data set from a logistic 
regression model?I need to manipulate parameters and so 
obtain my set of data.
I want to show the improve in analyzing binary data 
with GLM(binomial) model instead of classical ANOVA or 
NON-MODELS procedures(relative risk-odds ratio-Pearson 
test of godness of fit...)
Can you say me what is the right function to use?
Do you know any interesting simulation in the web?

Thank you.
Michele.