DumpContainer is cool, but it's not convenient to new a DumpContainer() and set the Content.
Please support Dump(string containerName).

Like this:

public static class DumpExtensions
{
public static Dictionary<string, DumpContainer> dict = new Dictionary<string, LINQPad.DumpContainer> { };

public static T Dump<T>(this T obj, string description, string containerName)
{
    if (!dict.ContainsKey(containerName))
    {
        dict[containerName] = new DumpContainer().Dump();
    }
    dict[containerName].Content = obj;
    return obj;
}

}

// Then I can simplely print 1-100 in 5 containers

void Main()
{
DumpExtensions.dict.Clear();
for (int i = 0; i < 100; i++)
{
i.Dump("", (i%5).ToString());
System.Threading.Thread.Sleep(100);
}
}