I have had one of these for over a year:
http://www.schwinnbike.com/products/...tail.php?id=53
Got it at the local W***Mart, $9.95.
The main number is fairly big but the button (right one) that changes modes is a little hard to push. Otherwise it works pretty good.
I also have a CatEye Strada Cadence. Its numbers are smaller and harder to see. I will eventually be replacing it (recycle to another bike) with one of these, which has a bigger display (have it, but not installed yet):
http://www.sigmasport.com/us/produkt...punkt=features
I have some of these:
http://optx2020.com/reading.cfm
one on each right eye side of my riding glasses so I can see the speedo numbers better.
Still need the 'cheaters' to read the fine print on stuff off the bike.