Some people take it and feel like dancing! I met an artist who was in the habit of taking K while painting - it would put him right into the zone for his work. People have really different reactions to drugs.
I did it a fair amount for a few years, it depends how much you take. In small doses it takes the edge off something like mdma and adds a "trippy" element. If you take a higher dose it is a full on introspective trip that can be quite intense and you aint going anywhere. It doesnt last that long per dose, maybe 1/2hours so less of a commitment than say acid, which can be more like 10-12 hours
Seems to be incredibly popular in UK and just like MDMA they are taking pretty high doses in general so you have teens needing their bladder removed due to abuse.