Collection was modified enumeration operation may not execute

Scenario:
I was writing a small SharePoint utility and was in rush for my next meeting.
When I ran my utility to test the first cut. I got the following error.

Error : [System.InvalidOperationException] = {"Collection was modified; enumeration operation may not execute."}

Code was like this

 foreach (SPListItem item in sourceList.Items)
{
          if(item["Title"]!="blah")
          {
           item["Title"] = "blah blah blah ";
           // Some more code
           item.Update();
          }
}

Reason:
While the error message is pretty clear and is not specific to SharePoint, I thought of posting. As you see I am looping through the ListItem Collection and modified the item itself which re-arranged the Collection itself. So next time SharePoint loop to get next item, you will encounter the above error.

Solution:
There can be 'n' solutions for this but this is what I did to fix it.
While looping I didn't modify the item but only copied its ID in a List and added an extra looping to get the items by ID and then modify the Item.

Modified Code:

 List<int> itemIDs = new List<int>();
foreach (SPListItem item in sourceList.Items)
{
           if(item["Title"]!="blah")
          {
             itemIDs.Add(listItem.ID);         
          }
}

foreach (int i in itemIDs)
{
      item["Title"] = "blah blah blah ";
      // Some more code
      item.Update();
}