My favorite is generating a sequential resultset of the numbers 1-4096 in SQL Server with this simple query:

;with [[[]][[[](_)as(select 1 union select 0),[[]][]][](_)as(select 1 from [[[]][[[] []]]][]]],[[[]][[[] _),[]][]][[](_)as(select 1 from [[]][]][] []]]][]]],[[]][]][] _),[[[[[]][](_)as(select 1 from []][]][[] []]]][]]],[]][]][[] _),[[[]][]]](_)as(select 1 from [[[[[]][] []]]][]]],[[[[[]][] _)select _ from(select row_number()over (order by _)from [[[]][]]])[[[]][[[](_);

/s