The basic pistol is fun to play with. Another option would be a 1377, no CO2 to fool with that way - but then some folks fall into the temptation to "improve" them, too. After 10 years my 1377 is sitting here waiting for me to finally flat top the valve. It's put a bunch of pellets down range and done so very accurately. Some of the best groups I shot were before putting the Crooked Barn breech on it, just shooting some old Daisy SpeedMax (IIRC) pellets that were sitting around. Even with the plastic breech I was getting one ragged hole at 10 meters. After putting the new breech on it, those pellets never shot that well for me again. BUT some others did.
There's a lot to be said for the Crosman 2240 in its factory guise. It's cheap, reasonably accurate and not too hard to shoot decently. With a bit of file and polish work on the sear and a bit lighter spring it can be made to shoot very well with only a bit of time spent smoothing it up. Since it's only a $50 pistol it's easier to convince one's self to dig in and experiment a bit. Replacement parts are available cheaply from Crosman so if you really botch the job up then it's not hard or expensive to return to factory specs.
There are some other cheap mods that one can do if one decides that one is capable of outshooting the pistol (most folks CAN'T outshoot a factory stock Crosman 2240 - because most folks can't shoot a pistol to start with). If you believe (or KNOW) that the pistol is not shooting as well as you are capable of then you can tighten up things a bit with some teflon tape around the barrel at the port, just enough to take up any slop there. Check the barrel for a good crown job and if need be you can recrown it yourself. None of this takes more than a bit of tinkering and many of us have the few bits and pieces needed just laying around so there's no outlay of cash.
If you'd like a cheaper plinking pistol then it's not too hard to buy a 1377 barrel and bolt from Crosman and turn it into a 1740. Same breech, same everything, just swap in the longer, smaller caliber barrel and bolt and you're good to go.
The Crosman 2240 is a good deal right out the door. A bit better deal (for not TOO much more money) is the already mentioned Custom Shop 2300KT. You can choose between the 7" barrel in 22 or 177 caliber or go with a longer 10 inch Crosman for not much more money. The downside to the Custom Shop pistols is that they come sans rear sight in the cheapest form. If you're good at fabricating things then you can put together a rear sight - or you'll need to put some kind of optic on top. For iron sight shooting the best bet is to go with their LPA MIM sight. - but now we're well out of the realm of the $50 pistol and pre-shipping cost of the 2300KT with a 10 inch barrel and LPA sight is right at $129. What do those extra $79 dollars buy you? They get you a steel breech, a steel bolt, a much better rear sight, a longer barrel which gives better sight radius for using those open sights, a better trigger/sear/spring setup. And (with the exception of doing some polishing on the sear) there's nothing you need to do other than use a drop or so of appropriate lube on each CO2 cartridge and shoot away to your heart's content.