My co-worker/internet personality Tom turned me on to Zenni Optical, where I can custom-tinted prescription glasses and a pair of clip-on sunglasses for about $20.80, shipping included. The internet is a magical place.
I lost my prescription immediately after getting my last 2 pairs of glasses (end of insurance), so I could never buy future pairs online for cheap :( I'm now wearing the ones I bought as a backup, and have been for about 3 years now.
The face on Ash in Panel 2 is exactly how I react every single time I go shopping for sun glasses. Vendors in shopping malls must be out of their damn MINDS if they think their going to get business selling $3,000 to $5,000 sun glasses!