Battlefleet Gothic
Battlefleet Gothic is a little-played specialist game made by GW.
it is set in some hell-hole corner of the galaxy where warp storms have stranded a bunch of ships from various factions and now their fighting over blackstone fortresses, old as hell space stations the Eldar built WAAY back in the day to deal with certain issues.
Some people still think that BFG is one of the best or at least most fun games that GW have ever made and anyone who says otherwise is likely to get a swift kick in the dick. Particularly assuming you just ignore the Necrons, and everyone playing is faintly competent then much fun can be had by all. Doubly so when the optional limit on assault boats is used so that escorts are worth a fuck. Any game that encourages you to plow through the middle of the enemy so that you can shoot all your guns at once has got to be pretty good. Also, the flavor of the game is pretty fucking awesome actually, what with the various planet demolishing shenanigans and just plain gorgeous rule book.
Also, in the land of 30cm range weapon batteries, the man with an unerring ability to guesstimate his Nova Cannons on target is king. Putting the 1cm hole onto a 3cm ship base at 100cm range and straight fucking up a cruiser is just beautiful. Although that takes a fair amount of skill. Alternatively this can be achieved by building your own board and making apparently random stars bigger and brighter and knowing the distances between them. In theory this is faggotry, but since not a single fucking person ever built BFG tables except the people that were crazy into it, this counts as homefield advantage, or at least is near on impossible to spot and as such is not really cheating.
factions
Of course this wouldn't be a GW game without the empire, their ships look like giant fucking Vaticans with warp drives and cannons. its rumored that in the lower decks there's like...villages of lost workers, but nobody gives a shit. According to the rule book they have massive fucking crews and apparently zero actual technology to move shells weighing hundreds of tons into gun breeches and such. The book shows slaves running on massive treadmills to move them about. Wouldn't your navy work better if you used like... machines or something ? If only we had a bunch of crazy ass priests who are fucking insane about technology on board to sort that shit out for us!.
In general, the imperials are good at torpedoes and nova cannons and other stuff. They also have 6+ front armor, which isn't that big of a deal, but its nice y'know.
Chaos
Pretty similar too the imperial ships, but emo'd up. Also a bit faster than their counterparts who still worship their corpse-god. Also have the most choice of ships, making them superior to any other fleet (except sometimes Necrons) if correctly built. For unknown reasons the chaos ships look totally different from the imperial ones, not just imperial ones with tentacles and spikes and crap. While this obviously helps people tell the ships apart, the explanation of 'Oh they are just old ships' doesn't stand up to more than 8 seconds of scrutiny. They later made some ship that were supposed to be the 'old' imperial ships that were bastard chimeras of both and they were ugly as all fuck and somewhat terrible, which begs the question why the chaos fleet is actually any good.
Chaos is good at having MOAR DAKKA on their ships, and using their speed to rock balls.
Necron
They have like 5 different kinds of ship and according to fluff are fucking nasty to fight. Also the most powerful fleet, second only to chaos (and only if the Chaos player very wisely chooses his ships, you on the other hand, have light cruisers that can blow apart battleships without a scratch), due to having the only armor saves of the entire game (no joke here) and a shitton of close-ranged weapons, thus being unkillable. The drawback is that if you lose even only one ship, your opponent will gain way more victory points than said ship point cost, something that can cost you victory if you are careless. They remain OP.
Eldar
Their ships look a lot like their vehicles- no surprise Eldar can't be original. With only about six ship in the original rulebook, they were somewhat gimped from the get-go. They have shiney fields of awesome to protect them from lances and the like, but gun batteries fuck them up so hard its retarded, particularly since they HAVE to dip into battery range to fire. Also, the cruisers were so frail and lacking firepower that they were worthless, so they were left with a fleet of escorts and while they were pretty fucking awesome for what they were, they just melted when they got sneezes at, the Eldar were pretty fail except in specific scenarios that let them abuse the fuck out of their movement rules. If the sunside edge is towards the enemy, you are fucked and there's just no reason to play.
Tau
The Tau have two choices of fleet. Their initial fleets were composed of refitted modular merchant ships and scout vessels. After getting their shit wrecked, they got together and finally built combat ships. Players have the option of the modular, adjustable, Merchant fleet or the efficient, effective Combat fleet. Names of all ships can't be pronounced.
Orks
Look like the most fun to paint, their ships are ramshackle at best and if you used gum instead of super glue to make them it would probably be more thematically accurate... and gross. In theory their random strength heavy batteries are pretty cool, it turns out that random translates alternately into 'pathetically ineffective whenever its important' and 'did exactly what any other weapon system would have done' inside the game. However, fleets of ram ships are pretty awesome, because nothing is funnier than ramming the shit out of people.