You might have heard that we Androiders have gotten an original Playstation (PSX) emulator in the market. It costs $6 US. Apparently, it is awesome. You have to supply your own ROMs and BIOS (like with any emulator), but it works with BIN,ISO,IMG,PBP,Z,ZNX, and Eboot formats. Also, it supports using a Wiimote as your controller. Wiimote + TV-out = grand nostalgia time. Anyway, here is a how-to on getting it up and running. Note that due to piracy issues, we can't tell you where to get ROMs or BIOS from. Nothing that Google can't tell you.
First things first - download psx4droidfrom the Android Market or AppBrain. You'll need a 'high-end Android' to run the games properly, which means the likes of the Nexus One, HTC Desire, or Samsung Galaxy S. It's worth noting, though, that the app is a work in progress, and you won't get perfect performance on any Android device.
Download the PS1 BIOS file 'scph1001.bin' from any number of sites - none of which we'll name here. All we'll say is that it's not hard to find, and that Google and YouTube are your friends in all things.
Ready your PlayStation ROM files. Once again, we're not going to go into specifics here. We'll assume that you own the original game and have made a ROM file as back-up.
Bear in mind when making your ROM that psx4droid doesn't recognise MDF files, so stick with the likes of BIN, ISO, IMG, and Eboot.
Plug your Android device into your computer and create a folder. Call it anything you like: PSX, PlayStation, PooperScooper. Anything. Put the BIOS file and ROM files into said folder, and alongside it create another folder called ROMS.
Boot up psx4droid and touch the PSX BIOS file option, then search for the 'PSX' file you just created. Select the .bin BIOS file. Now back up a step into the default 'Select ROM' section, navigate to the same PSX folder you created and select your ROM.
Hey presto - PlayStation gaming on your Android. Have fun!
Big thanks to pocketgamer.co.uk for the how-to!