I'm not religious but I've recently been giving up stuff for lent - it probably harks back to my mother making me give up chocolate for lent so that I'd appreciate the eggs even more
Last year I cake(freudian slip) gave up diet coke for lent and was successful, and it made me realise how much I didn't miss it/didn't want it. I've also given up fries for lent before and lasted 2 weeks! Unfortunately I worked in an environment where people ate fries every night!
So with regards to the holy aspect of it, I don't observe that, but I do use the period as a time to challenge some of my tastes and aspects of my life. I think this year I might give up shopping or something! I gave up diet coke at New Year and I don't eat fries any more and I don't really have any huge weaknesses that are standing in my way apart from the money front, so maybe recreational shopping is going for the chop this lent!