I'm currently doing a review of Advanced English Dictionary for the P900. Its a great bit of software because it gives you access to tons of data in your pocket. It includes encyclopaedic entries not just word definitions. The P900 version installs the dictionary on your device but its big, about 6.3 meg.
I got in touch with them with a couple of queries and found out they are doing a version for Series 60 and other J2ME devices. However this will be client server based (presumably using GPRS) to reduce the size of the install on the phone. It also includes some extra search options not currently available on the P900 version. They are looking for a couple of people to help them with testing this version and as I don't have a Series 60 yet I thought I'd post this here. If you fancy testing it, get in touch with [email][email protected][/email] mention you're from AAS.