This one specific topic was touched many times by Nokia N900 users for quite some time. eSpeacCaller was pretty good for me, but not sufficient for everyone  Now there is a solution for assigning custom ringtone to contacts from you phone book, only thing you have to do is installing mysterious Custom ringtones for your contacts application
After you have it installed for every contact in your phone book you can open Change custom ringtone settings from menu. When you open it you have choice from standard ringtones available on your N900 or you can choose any sound that you have in memory by pressing ‘More’ button, just like for standard ringtones for calls and messages.
As for me it wasn’t a big problem, I was handling this situation for over half a year without any problem, but it’s good to go back to some old habits, knowing who’s calling just by a ringtone. For some it’s more convinient to have it instead of synthesizer telling aloud your contacts names or nicknames. Finally we have one of the most wanted features in this high-end piece of electronics. Enjoy!
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MJ

We have talk about the amazing thing that the Nokia N900 is, about bringing a revolution on the mobile world and the integration concept. But now seems that having a full integration between your Nokia N900 phonebook and Skype, GTalk and other IM services has a dark side too.
Recently I have read a post were the writer warned about the Nokia N900 phonebook due to his experience. The thing is that when you delete a contact on your Nokia N900, you are also deleting it from all the IM services like Skype, GTalk, etc. But the Nokia N900 warned him about this by a message on the screen which it said: “Deleting contacts will also remove them from the server”. In that moment, the writer didn’t understand the meaning of the word “server” as the same way that the Nokia N900 meant. When he finished deleting the contacts was when he got it, the word server was referring to the IM servers, so all the contacts on his Skype and GTalk list disappeared (All this using the Delete Contact option, one by one).
Later he found the Delete All contacts option under the Settings options. And by using this option, it only deletes the contacts on the Nokia N900, not on the IM services.
I thought that it was a good idea to share this writer experience with our readers because it´s something that could happened to anyone and it’s better to prevent you from a big headache.
Here is the writer’s post if you want the full story.
“Tight integration with various Instant Messaging services (Skype, GTalk, MSN Messenger, etc;) is one of the great features of Nokia N900.
It’s super convenient. I crowed about it in my first impressions review of Nokia N900.
You just enter your IM login details, and all your contacts from them appear in the address book. It might take some work of merging these contacts, especially for the incomplete profiles, but then they are there, and when you want to talk to someone, you just have to select  how – Skype, GTalk, SMS, e-mail or phone call.
It just works, and changed my …

The title may confuse you but that it´s because the Hermes app is underdevelopment.
Do you remember when you opened a new email account and you needed all your existing contacts on it? Annoying it was. But you can get this trouble solved by some kind of sync. Then something like that happened when updating to your phone contacts. Once again a waste of time. Imagine now when you receive your Nokia N900 and you want to sync all your contacts to bluff about your new N900. But I’m not only talking about the phone contacts, also about your Face Book, Google Talk, Gmail, MSN, Twitter, Skype, etc. In my opinion, this is an important issue and future need of the N900 users that I hope some developer would face to solve somehow.
Andrew Flegg who is developing the Hermes application, got ahead of this need, and created Hermes. Hermes is an application that simples sync the info of your Face Book and Twitter’s Contact with your N900’s contacts. Only some info like birthday, photo, etc. because due to the Face book privacy politics, they can´t send you personal info such as phone number or email.
The app is promising so let´s wait to see the official release. Finally, I want to highlight again that this is an important situation to be solve, and the one who can came up with a really practical and complete solution app would be adored and the app would be on every N900. Hermes has pointed in the direction.

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