Until recently I've been using an old scientific calculator that my dad bought
The battery died recently and I think this might be a good excuse to buy myself a new one like everyone else uses.
I'm looking for a very standard make and model, something that is very commonly used. What do most people in science/engineering use?
PS: I'm getting lot of recommendations for the TI-89. So when you say TI-89 do you mean the old one or the new one ("Titanium")?