I generally do this in 1 regularly occuring situation. If there are loose players at the table (which is generally the case at the lower buyin SNGs, 33-, depending on the day and time), and I'm in early position. If in late position, I play AK/AQ straightforward and raise.

If in early position, it'll be too likely I'll get 5 callers and play AK/AQ out of position multiway. Limping is intended to control the pot size the way I want it...since my raise can't make this heads up and I don't like to have to put in 1/4 my stack (800-90preflop raise = 710; 4 callers gives 360 pot, 180=half pot) as a 1/2 pot continuation bet (even when I flop TPTK), and if I check someone is going to always bet no matter what.