Fix him a nice meal and offer him a blow job. Be glad he comes home at all.
*grin* JK, baby.. Just more macho humor. Is he just venting steam (which I've done a lot of times)? Has he offered you the chance to join him? Is that the only time he has "with the boys"? Just trying to be reasonable. If he's being inconsiderate, then plain talk is what's needed. Don't look for "payback". Just get him to see your point. A frying pan up side the head works well.
Then kick him to the curb, and come hang with me and be appreciated for the love goddess you are. ;-)
A serious discussion followed by spying if you felt he is lying, once you get a proof you can determine how to respond. Ps. Have you not discussed this with him yet?!!! I mean, does he come at 3 am without providing any explanations like it is something normal?
Nah, you should make it clear to him that it is a big deal and that he has to tell you where the hell he goes every night ! You have to show your rejection and resentment about it, I'd make his life hell but also make it clear that this hell is because of his stupid acts - I don't know how far you have gone with this situation, that's why I hope I am not giving you the wrong advice, but if it is situation that's just starting then you might wanna try solving it by being more positive and showing him that you actually "want" him to be home for the sake of wanting him not restricting him, it is always good to try to solve things positively at the beginning, if this does not work, then you show the other face.
Depends what he's been doing.
You should just come back at 6 am one day and see if he notices.
seriously lock him out and leave his things where he can get them. for a while.
Sounds like you dont trust him at all