I still have a microscope on my desk. A recent Nature Methods paper let me just hold my digicam at the eye viewer – without any adapter the results are remarkable, see the HE stain of a blood smear from an asthmatic proband.
Seems, that you can spend a lot of money for flow cytometry although this can neither visualize cells repeatedly, nor collect a great deal of light (due to the microseconds where cells pass a detector) nor even get cell shape, size and intracellular localization of flurescence. But hold on, there is great open source microscopy software (in addition to my essential photo list — often in combination with Matlab or Physics Analysis Workstation :
μManager Open Microscopy Environment ImageJ CellProfiler CellVisualizer and CellID