Hi folk.
Herewith the requirements for VMC uncontrolled Airspace.
Local Flight (not exceeding 20nm radius from point of departure)
Not above 500 feet (Demon, you are quite right, the LS/1 rule was 1000feet, but has now been reduced to 500 in the CAR's)
No instruments what so ever are required
Above 500feet AGL you need an Alitimeter, and ASI. Note that if you go higher than 1 500feet AGL, (depending on your proximity to Controlled Airspace, (ie local transition altitudes)you are entering Flight Level stuff. Therefore you need to have a radio to speak to Area Information, and obviously an alitmeter that you can set while in flight for FL (ie 1013Mb)
Controlled airspace (NOT international Airports), but o.k. for eg., Wonderboom, East London, Virginia etc.,
Radio for 2 way communication
Sensitive, adjustable sub-scale Altimeter (ie it must be calibrated and you must be able to adjust -while in flight- the Mb pressure scale)
Air-Speed indicator
Cross Country flight
Compass, plus the above depending on your planned height to be flown on the cross country, and whether you are going to enter controlled airspace or not. For eg on my flight to prieska last year, I could have flown the entire flight with only a compass and nothing else, not even a radio.
International Controlled Airspace (eg Cape Town TMA or CTR)
All the above plus mode C Transponder
In a nutshell, the total instruments you may need, depending on where you intend flying, will never need to be more than, and this combination will allow you to fly into the most controlled and tight airspace (depending on your radio skills

)
Compass
2-way radio
Altimeter
ASI
Transponder mode C
Anything more than this is NOT a legal requirement, and merely adds to flight and engine management.
Hope the above helps.
Regards.