Can a gay or lesbian go to heaven?

Someone can accept Christ, not change his lifestyle, and still go to heaven. The Bible teaches that if someone has truly accepted Christ into his life, nothing can keep him out of heaven. John 10:28

There is only one sin that is unforgivable.. That is the sin of not believing and not receiving Jesus Christ into your life. A gay or homosexual person CAN accept Christ, just as an alcoholic, a drug addict, or a mass murderer can accept Christ.
God made everybody a certain way for a reason. Why would he make you this way if you weren't allowed in heaven. If you change to be gay or lesbian for somebody then that is a different story because you change how you were born. Anyway if you follow god's rules then you should be set because there is a lot more people who do bad things and your not doing anything bad.

A Catholic Answer (Catholics in union with the Pope)

Gays and lesbians are just like straight people -- we are all fallen human beings. There are straight people with brutal tempers who sin against charity and justice habitually. There are straight people who are congenital liars and would sell their own grandmother to make an extra penny. There are straight people who are cowards and refuse to face up to their responsibilities. God made us all; He loves us all; yet we are all fallen; all have fallen short, some in one way; some in others. Some of us don't even realize how short we've fallen. Whatever tendencies we may have that may cause us to offend God - whether temper, greed, or lust -, we must strive to overcome these, with God's help, and live lives of holiness.

Persons -straight - who have fallen, and who repent will be welcomed into Heaven.

Gay answer. Yes lesbians and gay men go to heaven, its a Night club in London. If we are talking about the spiritual place then most definately, who else but gay men will make it fasionable and keep it clean?