After update to GRJ90 I can no longer use WiFi hot-spot
Sprint tells me that I need to pay for a hot-spot plan for $30, but there has to be a way around this besides rooting my phone and putting Cyanogen on it.


Sprint clamped down and disabled the previously free built-in tethering with the latest update. If you want USB tethering you can try PDANet, but wifi tethering will almost certainly require you to root, as it does on other devices.

Even with root, you don't necessarily need to use CyanogenMod if you don't want to, though; you could just as easily install a free tethering app (one example). This has been covered here a lot, in fact, so you might want to take a look at any wifi tethering apps noted in other questions.

See also: Is there a way to enable WiFi-tethering without root access?