I’m an outspoken advocate of always using a clustered index on each and every table you create as a matter of best practice. But even I will agree that there’s a case for using the odd heap now and then.
Know your collation orders
We’ve discussed earlier on the effect of using SQL wildcards, such as ‘%[a-z]%’ with different collation orders, particularly case sensitive ones. Here’s another take on collations, and how different collation orders can sort text differently.