Romans 14 : 20-23
(20) Do not destroy the work of God for the sake of food. All things indeed are pure, but it is evil for the man who eats with offense.
(21) It is good neither to eat meat nor drink wine nor do anything by which your brother stumbles or is offended or is made weak.
(22) Do you have faith? Have it to yourself before God. Happy is he who does not condemn himself in what he approves.
(23) But he who doubts is condemned if he eats, because he does not eat from faith; for whatever is not from faith is sin.
I believe that alcohol was created for our pleasure, and is in itself not a sin. However, there is a question of WHY you drink, or who it will affect. Most churches have taken such a hard line on drinking, that seeing Christians drink immediately makes most observers view them as hypocrites. It is easy to drink simply for the buzz, or to escape, or any number of reasons that does not glorify God, but serves our own desires.
Being "drunk with the Holy Spirit" describes what you might see in many Pentecostal churches (and a few others) if you were an outside observer. It's hard to describe if you've never experienced it, but it's one of those things you will know when you see it. It is not phrased in the Bible specifically, but probably refers to Acts 2:13-21
13 Some, however, made fun of them and said, "They have had too much wine."
14 Then Peter stood up with the Eleven, raised his voice and addressed the crowd: "Fellow Jews and all of you who live in Jerusalem, let me explain this to you; listen carefully to what I say.
15 These men are not drunk, as you suppose. It's only nine in the morning!
16No, this is what was spoken by the prophet Joel:
17" 'In the last days, God says,
I will pour out my Spirit on all people.
Your sons and daughters will prophesy,
your young men will see visions,
your old men will dream dreams.
18Even on my servants, both men and women,
I will pour out my Spirit in those days,
and they will prophesy.
19I will show wonders in the heaven above
and signs on the earth below,
blood and fire and billows of smoke.
20The sun will be turned to darkness
and the moon to blood
before the coming of the great and glorious day of the Lord.
21And everyone who calls
on the name of the Lord will be saved.