Hello everyone , i try to retrieve the user's id , like an IP adress or an email or the google login , my program should pick some infos for a database's purpose . If this is possible without a permission , i tried the taifun pickup but it prompted me , is there a plugin somewhere that could not do that ? Thanks guys for your answers , you rock ! 
Since you are from Europe you have to abide by European laws in collecting data from users. So you will have to explain what you collect and what you do with the info.
ok thanks for the reply