planned SMS functionality

Hi all, my name is torsten, living in germany. Last week I released the Westors Elgg Manager plugin with a comfortable AJAX user interface to manage users friends, groups, messages (ahhh! messages, so it can be extended to SMS??? YES!).

The frontend part is interesting, but not such a big deal for me, I already have this running on a site in an early release. I have a connection to a german SMS gateway, which receives the messages via http requests. This screenshot shows an example from my existing website.

SMS preview

There are some nice features, like extra log SMS etc. On the client side I check the sender numer to prevent from sending with a number of someone. You can schedule your messages and something else in the future. (thinkable are things like automatic birthday greetings and personalized messages with variables for the name... are nice features)

Answer functions to Elgg are thinkable... I have to check this out, if this would become a need.

I see the following problems, if I would extend my plugin with SMS and enable this for the world:

Note: I have to pay for the SMS. And probably you have to pay (or find a provider, who is able to deliver SMS in large amounts for free to the world - I would say, that is a nice dream).

The price is dependend on how much SMS you send in a month. The price is also dependend on countrys, where the SMS go to. And not all countries are easy to handle. As far as I heared from my provider, espacially in the US there are only some carriers who deliver SMS without problems.

What I could do: I develope this plugin usage ready, and I preconfigure the SMS provider that I use. I will give you the link to the price list at the end of this post.
Than you are available to have a contract with this provider or not. And if you need to, I could customize the plugin for other providers, if necessary.

Here is the url of prices of my SMS provider:

http://massenversand.de/site/1smsversand_pak.asp

Your feedback is welcome.