Best way to add "smack" on snare

A transient designer can help with a poor sample or bad recording. For a well recorded snare, compression and judicious EQ is all that is needed.
 
Regards,
Dan

My approach (and I suspect bapu would corroborate) has been to accumulate a large collection of drum samples and then find a snare that's got whatever quality, e.g. "smack", I'm after. Gather enough samples and there'll rarely be a need for further processing.
 
Analogue Drums and Drumdrops both offer a wide variety of inexpensive but great-sounding Kontakt-based kits. Many of my favorite individual drums came from Drumwerks, although many were not in a Kontakt format and required making an .nki for them. They have a bunch of cheap snare samples (most are 5 bucks, the whole collection is $20). There are a couple other companies whose names I can't recall right now.
 
I've also been known to layer a sidestick, stick, clave or handclap sample over a snare if I really want a sharp attack.
 
And, as noted above, if all else fails a compressor or transient shaper can be called into duty. That would be my last resort, though. I'm more likely to use parallel distortion on the snare. Favorite distortion plugins for that are Redopter and Devastor from D16, or Fabfilter Saturn.