Side Space Skyscraper is tested on wordpress version up to 3.4.1 and works fine. I suggest you to use this plugin with fixed width themes, to works more effectively.
How To Install Side Space Skyscraper?
Installation process of this plugin is same as of any normal wordpress plugin. Download this plugin file and install it then after activation go to WordPress Dashboard >> Settings > Skyscraper and add your ad block code and finally click save button. See the screen shot below.
This is a very light weight plugin with total file size 8.34kb only. You can download Side Space Skyscraper 1.0 at download button above.
Note: The present release of 'side space skyscraper' is 1.0 and is in beta stage. The stable version (1.1) will be released next month. As it's the initial release so there may be some confliction or other issues as well, If you are getting anyone please let me know.