I've not tried to do so, but I'm sure it can be done.
You'd of course want to download the SWT libraries from
eclipse.org/downloads. Note that the SWT only download is towards the bottom of the main download page.
Then, as instructed on the download page, you'll want to mount all of the SWT jars in your NetBeans project. The trickiest part will be adding the SWT JNI library to the java.library.path. Again, I've not tried to do so, but it's probably pretty easy to get it to work.
To run a standalone SWT application, add the swt jar(s) to the classpath and add the directory/folder for the SWT JNI library to the java.library.path. For example, if you extract the download below to C:\SWT you would launch the HelloWorld application with the following command:
java -classpath C:\SWT\swt.jar;C:\MyApp\helloworld.jar -Djava.library.path=C:\SWT HelloWorld
[ February 03, 2004: Message edited by: Dirk Schreckmann ]