Solaris Enterprise System
So, Sun made an big announcement today: You can download almost any software from Sun for free. So you can try out the stuff, develop for it or do some experiments with it without the hassles of expiring demo licenses or the need to buy some licenses. You only have to pay in the case you want support (for example for going to production). You can even use it in your production system without paying for it, but this would be something for the die-hard-administrators, because you get only the bytes and support from the community.
With this step you can use the commercial-grade software from some like the components you find in a linux distribution. (When you find them in Linux e.g. there is no cluster framework equivalent to SunCluster in the linux world.) Use them, try them, and when you are ready for prime time with your service, buy it. You can download the stuff right here
I think it´s a very important and very good step in the war for developers and mindshare. Or to cite Paul Murphy:
Ultimately the contest between IBM's Cell, Sun's CMT, and Microsoft's traditional PPC will come down to developer and customer loyalties -and in that battle it doesn't get gutsier than this.
Thanks Sun! it's a big win for open source, and I hope an equally big win for you.