ReSharper 4.0 has been released and it has a 30 day trail available.

ReSharper 4.0 features full support for C# 3.0 and LinQ.

It also has some new refactorings built in, and promises to be faster.

I have been using the beta version on Visual Studio 2008 for a while, and I did not notice any errors with the version I had.
A great thing about it, is that it can help you in learning some of the new C# 3.0 features, by suggesting refactorings that
take advantage of the new features.

I was shocked by the cost to upgrade from 3.0 to 4.0 though: $249. That is excessive.
Around $150 – $100 would be reasonable and expected.

For someone who has been using ReSharper since pre 1.0 it felt a bit like a slap in the face. 

 I hope jetBrains might drop the upgrade fee, or at least have an introductory upgrade offer.

UPDATE: I received a message from Ann of Jetbrains, saying that there was a minor issue with the web page
that had the pricing, and that the correct pricing is now available. This brings the cost down to $209 for Full version 3
to Full version  upgrade, and a good $149 for C# 3 upgrade to C# 4 upgrade.