Buy one of those turkey fryer bases. Put it under your water heater and everytime you want to shower go down and fire it up 3-5 minutes before hand. Will save you money also.
Coworker/Friend has his water heater go out ~3 months after buying his first house. He was heating water on the stove and using a camping shower for around a month until he finally replaced the heater.
Yes, he was cheap. Yes, he was in his mid 20s, and yes, he was single.