Two points:

Hetalia has us covered.

I know this isn't a TV series, but the friendship between these two was so well (under) played in the movie and never allowed to stray into something tacky.

G'Kar and Londo from Babylon 5. Despite being polar opposites temperamentally and literally at each other's throat more than once, they developed a deep affection for each other that lasted till G'Kar sacrificed his own life to end Londo's suffering from the Drakh Keeper parasite.

SG-1.

I see your Bashir and O'Brien and raise you one Bashir and Garak.
Often the best friendships are based on learning from difference and
adding novelty to the repertoire. :)

Recycling time!

Can't believe those two are still missing.

Bashir and O'Brien.

Names: Batman and Superman

Why their friendship is amazing: They're two sides of the same coin. Batman may resent that Superman doesn't always appreciate his powers, to the point of being naive, and Superman sometimes wishes that he was as uncompromising as Bruce, but they usually bring the best out of each other. And…

I think Science Bros trumps all. Iron Man aka Tony Stark and The Incredible Hulk aka Bruce Banner both from the Avengers!

At work so can't post an image, but i'd for sure say the Blue and Gold. Booster and Beetle Baby!

I read the title of the article and I knee jerked to wanting to post a picture of the alien probe.

The cetaceans have a lot shit to settle with us once they get their power armor:

You're missing the infamous "Buggre Alle This" Bible. To quote noted Biblical Historian A. Ziraphale:

I already posted Indy for archaeology, but Walter is a close runner-up in the field of... whatever we need this week (magical TV doctorates FTW). Self-medicating your crazy with your own home brews is always a bad sign.

Yeah, they should combine the matryoshka with the iron maiden. Fun for the whole Addams family.

I can't help thinking that Gomez would be perfectly fine with being nested inside Morticia.