I've found myself thinking, "Why can't I have this sort of experience on a handheld?" The technology is certainly there; both the PSP and DS have, in some form, online functionality, and it's only going to get more robust from here. I tell myself that it's only a matter of time before we start seeing games that, at best, rival the experience we get from traditional MMOs, or at the very least, somehow interface with the games we're already playing. Rather than keep fantasizing about what could be, I've utilized my limited vision and imagination to create a list of likely scenarios. Take them or leave them as you will.
#1: Massively-multiplayer takes on popular handheld game-styles
I've been playing Castlevania: Dawn of Sorrow a whole lot lately, and maybe it's my imagination, but I've been seeing a lot of game elements that would be easily-translatable to an MMO experience. For instance, a few days ago, I acquired a power-up that, when equipped, caused my character to do extra damage to enemies if I hit them from behind. Kind of like a backstab ability, the kind that thief-classes in MMOs have, you know? Yes, it's a bit of a stretch, but c'mon -- how cool would it be if, say, the Castlevania castle were crawling with dozens of other players, and you could team up with them to tackle difficult bosses? Or better yet, if you run into someone wailing on a Gorgon in the Garden of Madness, you could sneak up behind him, and bombard him with boomerangs. Everyone would have a little personalized character sprite, unique abilities, and the developers would throw in some kind of common area where people could trade stuff and jump up and down constantly. It would be great.
Hopefully, what we're imagining won't require something like this.
2D exploration-heavy adventure games aren't the only handheld standbys that could benefit from this, either. As blas¿ as the genre may be at this point, hack 'n slash action RPGs are always a sound contender for this kind of thing. Sure, we haven't seen a whole mess of them on handhelds thus far (apart from the middling Untold Legends by Sony Online Entertainment), but something tells me that the genre is ripe for an explosion on these types of platforms. My biggest wish, though, is a persistent-world Advance Wars game, in which you build your own armies (maybe with some kind of Warhammer-style points system), and join up with allied generals to defend territories under your nation's control from invaders (who will be real players, of course). It's most definitely a pipedream, but damn if it wouldn't be hot.
#2: Handheld software that ties into traditional MMOs
Let's say you have a character in MMO X. You log out for the night, but you want to monitor some stuff that you have up for sale on the in-game bazaar. When you go to bed, you bust out your PSP or DS, pop in your copy of MMO X's Handheld Supplement and track your goods in real time. Did some jackass undercut you? Well, undercut him right back! In your pajamas and silk sheets, no less! Or let's say one of your character's pets has been lagging behind in levels. This kind of software could feature specific mini-games to get it up to snuff.
It couldn't in any way invalidate the processes you go through in the actual game; that is to say, in the previous example, your pet would only be able to level as high as it would if you'd have done it in the real game, and you can't unlock and cool abilities that aren't available to people who don't use the handheld software. But it sure would be useful. The same thing could apply to under-utilized weapon skills, and the like. If the publisher made it so that the software was relatively inexpensive, and cost nothing on top of the MMO's regular subscription, then I could see a great many people using this. Sony Online Entertainment seems to be pursuing PSP development pretty aggressively. Maybe they will be the ones to do it first.