I know, I know... its kindof odd to post about a glasses company.  But hear me out.  If you need glasses, this is a great place to pick up an extra, great quality pair.  $8!  Not a typo.  I actually have a couple pair of the $8 ones and they work great.  I mostly use them to watch TV in bed or stow in the glove box of my car just in case because I have contacts.  But still...  they're great quality for the price.  The only downside I can think of is that it takes a little over a week to get them.  You need to know your prescription, and pupillary distance (I used a ruler and measured my own PD).  But if its an old prescription and you don't want to bother getting it renewed, no big deal.  You don't have to prove it to them, just put in whatever numbers you want and they'll ship em.  Your decision, your fault if they don't work.

Really the main reason, I posted this is because I've sent this information to a bunch of people and now I can just link to this article.  Enjoy!

Zenni Optical