In reply to JuneBob:
Do you want easy paths, or is rough ground ok? Clogwyn Mawr above Capel Curig immediately springs to mind, then Crimpiau just beyond it.
If you want closer to Snowdon/Yr Wyddfa then Moel Berfedd and The Horns (as the OS map calls the ridge between the Pyg and Miners' paths) are both nice mini-mountains.
And Clogwyn y Garreg from Rhyd Ddu is a great little hill. Only small but excellent views.