In recent years emulators have become increaingly popular for all computing operating systems. Often they are a way to allow people to relive memories from their past, or run programs from legacy computing systems. On Series 60 phones the emulators allow for all of these, but the most popular are for running games from retro systems. Emulation allows you to access the software catalog of old systems meaning that potentially you can add the ability to run thousnds more programs to your phone by installing an emulator.
In order to run a program you need a ROM image of it (i.e. the program files). These are often still copyrighted and therefore commercial programs from the past (for systems such as the Gameboy etc.) are not readily available. Certainly you will not find illegal roms distributed with the emulators. Almost all platforms do however have public domain roms. These are roms that are copyright free and can be freely distributed. The legal situation differs from system to system. For example the Spectrum emulation scene is not only one of the biggest, but one of the most 'legal'.
The Gamebody from Nintendo (the predecessor to what many people see as the N-Gage's main competitor) is one of the most widely emulated platforms. For Series 60 there are two options. Goboy from WildPalm comes into two versions. The basic option is freeware and emulates both the Gameboy and the Gameboy Colour. Goboy Plus add support for sound, the ability to run games directly from Zip file (saving valuable memory space) and allows you to send ROMs via bluetooth or IR to other phones. GoBoy Plus costs $10 to register. Gamephone from Infinitouch is a commercial alternative. It inlcudes advanced support for managing game files and full sound support. GamePhone costs $12.95
E32Frodo, the C64 emulator for Symbian OS. It was ported from Christian Bauer's original Frodo for Amiga. The emulator is free, including free source code as well. The Series 60 version was ported by Hannu Viitala. The binaries and the source can be downloaded from the project homepage.
ZXBoy from WildPalm software emulates the Sinclair Spectrum 48K and 128K. As well as support for various different input methods, save games, pause games, redefinable key support, and sound support the program includes a game browser which allows you to download new rom files over the air directly to your phone. Because of this ZXBoy has one of the most easy to use emulator set ups for the Series 60 platform and I recommend that beginners start with this (espeically if they remember the Spectrum). ZXBoy costs $10, sounds and the game browser are only actiavted once you register. Spectrian from White Cloud Software emulates the Spectrum 48K / 128K / +2 / +2A . It supports the Z80, SNA and TAP formats and has a keyboard option so you can play text adventures. This emulator has some of bext input option and controls of any Series 60 emulator. Spectrian cost 15 Euros and a trial copy can be downloaded from thier website.
Spectrum ROMS and more information about Spectrum emulation can be obtained from World of Spectrum.
NES (Nintendo Entertainment System)
YewNes is a NES emulator. In other words, it lets you play Nintedo 8-bits games on a Nokia S60 mobile. You can play more than 1,000 nes games on you mobile. It costs $23 to register, the registered version includes support for sound. A trial version can be downloaded from the author's website.
Mame (the Multiple Arcade Machine Emulator) is an emulator of arcade games for the PC, which has been ported to many platforms. The Symbian port of Mame is called EMame, and was first released for Psion and Ericsson devices by Peter van Sebille. The Series 60 port was made by Staffan Ulberg. MAME has more support for more than 1000 programs. There are two versions of the emulator, the standard version and the micro edition. The micro edition is intended for low memory Series 60 phones (like the 3650 and 7650) and supports only a limited sub set of games. The binaries and source code is available from the author's website.
fMSX is an MSX emulator by Juha Riihimäki adapted from the fMSX/Unix 2.7 source code. MSX is an 8-bit home computer that first saw light in 1983. With this emulator you can play hundreds of games available in the web for the MSX platform. The binaries and the source code can be downloaded from the author's website.
There are also a number of projects in development. One of these is a Neo Geo Emulator which is currently under development.