First, you should go look at the lists.
Now, in the Top 10 Most Popular Games we actually have 11 titles, because of a tie at 10th place. Of those eleven, only Donkey Kong and TRON haven't received real emulation rereleases. Still there are many, many ports of Donkey Kong which are worth playing. (I tend to favor the NES version.) Which means only one game, TRON, isn't available legally. That's a shame, and I have doubts that it will ever be emulated legally somwhere.
Update: As Alex notes in the comments below, TRON 2.0: Killer App for the GameBoy Advance has both the original TRON and Discs of TRON as bonus games. Certainly not emulation, but quite possibly good ports. I'm going to pick this up as soon as I can to see how it works.
Of the Top 10 Collected Games, all except Donkey Kong are emulated somewhere.
Now, if we look at the Top 100 Video Games (as selected by the KLOV staff), there are many notable games not emulated:
- Computer Space
- Death Race
- Sea Wolf
- Lunar Lander
- Star Castle
- Donkey Kong
- Donkey Kong Jr.
- Space Duel
- Dragon's Lair
- Track and Field
- Indiana Jones & The Temple of Doom
- Double Dragon
- Street Fighter
- Bad Dudes vs. Dragon Ninja
- Golden Axe
- Golden Tee Golf
- Captain America and the Avengers
- King of Monsters
- Terminator 2: Judgement Day
- Lethal Enforcers
- NBA Jam
- Daytona USA
- Area 51
- Soul Edge
- San Francisco Rush
- House of Dead
- NFL Blitz
- Gauntlet Legends
- House of Dead 2
- Time Crisis II
- Ferrari F355 Challenge
- 18 Wheeler: American Pro Trucker
- Gauntlet Dark Legacy
- Ridge Racer V
Sure, there are lots of games that aren't here. Hundreds of games are not available in legal emulated form, and for each game there is someone who wants to play it. But doesn't the list of legally emulated games cover what most people want to play? And beyond that, don't accurate ports further lessen the need for illegal ROM use?
Well, quite simply, the popularity of games is not the same as their importance. In his book, "Free Culture", Lawrence Lessig talks about a similar problem with film. Due to constant copyright extensions, the term of copyright exceeds the shelf life of film. There are hundreds of films that are literally turning to dust on the shelf and will no longer exist soon. Many people would love to study these films and would fund their convsersion to DVD our of their own pockets (it can actually be done quite cheaply these days). But they have little commercial value, so the studios just don't care.
On a more personal note, my favorite arcade game of all time is Wonderboy in Monsterland, and I'm awfully glad I don't have to wait for Sega to decide that its important enough for me to be able to play it.
Casey, I'd be interested to know if you've tried any of the Wonder Boy in Monster Land ports? Wikipedia says that there are several: Sega Master System, PC-Engine, Commodore 64, Amstrad CPC, Sinclair ZX Spectrum, Commodore Amiga and Atari ST.
At least the Amiga and Atari ST should be capable of near-perfect ports, I'd imagine. Of course, much depends on how skillful and faithful the developers were. Screenhots of the PC Engine version (which apparently has a hack to put it in English) make it look reasonable. The SMS version actually looks better than the Commodore 64, which surprised me a bit.
I bet all of these are cheaper than the real arcade hardware, but I could be wrong. I haven't taken the time to price originals of these ports versus buying the just the hardware ROM version of Wonder Boy in Monster Land.
Anyway, I'm in a similar situation. I'd like to play Two Tigers, but it hasn't been released in emulated form. However, there is a clone made for the Commodore 64 called Island of Dr. Destructo that I am seeking. I played it back when I was downloading Commodore disk images, and found it to be a reasonable approximation of the original. So, instead of downloading the ROM, I'm at least seeking out an alternative.
Tron is available for the GBA, along with the Deadly Discs game, in "Tron 2.0 Killer App." Granted, you have to buy the crappy killer app game, but it is available.