Rent/WMG

Collins is on something throughout the whole movie, or at least on the first Christmas Eve
Need proof? Santa Fe. Think about it.

He did marijuana on-screen during one throw-away line in "La Vie Boheme," so the weaker version of this theory is true in the film.

It's not that farfetched an idea.

Angel is Santa Claus.
...So Santa DO NOT WANT.
 * Could have resurrected in a different form though ...

Mark is Bi

 * And has the hots for Roger.
 * This isn't Canon?
 * Maybe in Fanon
 * The actors of said in the recent Australian production hooked up.

Rent is just Newsies with AIDS.
Both are about people refusing to work (some of them with valid reasons), both have a song called "Santa Fe" praising the city that neither singer has been to, and both feature a main character's supposed betrayal that was actually to help the cause. The characters line up, too:
 * Roger = Jack (both harbor dark pasts, bail for Santa Fe, & come back to their friends & loved ones).
 * Mark = David (both are Jewish & take care of Roger/Jack).
 * Mimi = Medda (duh) + Sarah (Roger/Jack's love interest).
 * Angel = Crutchy (the one character everyone likes gets neutralized halfway through both stories & shows up again in the last minute).
 * Collins = Boots (friendly, mischievous black guys).
 * Maureen = Spot or Racetrack (a little more talk than action).
 * Benny = Pulitzer or Weasel (this one's kinda weak, I admit).
 * Joanne = ...Um, I can't think of a character that serves her purpose in Newsies...for that matter, I can't think of what her purpose is in Rent, other than to sing the awesome counterpoint on "I'll Cover You (Reprise)" that no one else in the cast can hit.
 * And Take Me Or Leave Me. And Seasons of Love (In the movie). And Tango Maureen. And...
 * And so Mark isn't with Maureen.

Certain songs were unfinished before Larson died.
I steadfastly refuse to believe that "think twice before you pooh-pooh it" is anything but a temporary lyic. It even breaks up the rhyme scheme.
 * ...Except that Larson died the day before the play premiered. It would've made no sense to randomly change the song the actors have been rehearsing for months on the night of the premiere.
 * Larson died the day before the first preview at New York Theatre Workshop. It's common to do rewrites during previews; considering that the show was already collecting buzz for a commercial transfer at that point, it's quite likely that Larson (and Michael Greif, and Tim Weil, and everybody else) had a long list of probable revisions to make.
 * This is true. I saw a documentary about Jonathan Larson and it said he was working on the show up until his death.
 * Yep. And people who knew the show and Jonathan personally say that, if he hadn't died, he would have continued to make a ton of revisions. The man was always looking to make his show better.

Angel is genderqueer.
That's why Mark doesn't know whether to call Angel "he" or "she" during the funeral, and why Angel dresses as both a man and a woman at different times.
 * Makes sense to me. I always figured she was in the grey areas of gender.

Mimi was pretending to have AIDS.
AIDS was becoming more sympathizable as drug use was becoming more scorned, and she could take advantage of that if she pretended to have AIDS and downplayed (or outright hid) her heroin addiction. If she met and became involved with someone who actually did have AIDS/HIV, it would give her a way to start a relationship that would feel meaningful and eventually fulfill the death wish that she had until  (a death wish which was at least very, very vaguely implied in the play, if I'm not reading too much or too little into parts of her character). Using prescription-grade stimulants (amphetamine-type) under the guise of AZT would help her counteract the more obvious side effects of heroin use and withdrawal while still leaving her to her weakening and wasting away. This would only work on people who walked into it assuming she was telling the truth and didn't know about the heroin use or who assumed she got AIDS as a result of something like needle-sharing (because who would ever lie that they had AIDS?); a former heroin addict and current AIDS sufferer knew and/or assumed that she was a heroin addict didn't realize she (supposedly) had AIDS until she stopped for an "AZT break". Her collapse on Christmas Eve, which I assumed to be an overdose? Was just an overdose.

Despite creating and (on a whim) making a case for the guess as an Alternate Character Interpretation, I didn't believe this myself until I came to this point: If she had AIDS, why would Benny sustain a relationship with her? It's not for sex, since nothing was ever given to indicate that he had AIDS/HIV (Yes, I do understand that even back then when treatments weren't as advanced as they now, many people were willing to trust thin, easily-broken latex barriers for long-term protection against this sort of thing). Status? She was a possibly-former stripper- or "S&M dancer"- who last year had the purported best hindquarters in the area but was canonically wasting away. A relationship built on love and mutual respect? Unless they both felt like lying about it in the same way, for some odd and so far obscure reason, this is definitely not the case. Spite? He didn't seem to care enough about Roger in particular to take her away with the sole purpose of causing him pain. The only reason I could figure for their relationship as it was shown (aside from the above parenthetical) was if Mimi didn't have AIDS and Benny knew.

During "What You Own", Mark is considering suicide.
Throughout the song, he's been singing about "living in America". Then, in the film version, he's standing on the edge of the roof and declares, "I quit," and switches to singing about dying for the next verse. It might not come across like that in other productions, but the fact he's standing at the edge of a roof in the film suggests he might be thinking about jumping.

Angel is male-identified
There seems to be debates about hir gender. It seems like ze only uses female pronouns in drag, which is a common things for drag queens and crossdressers.