Our favorite multi task 'stick' system is the STIHL KombiSystem using the 4Mix technology in the powerhead. They offer great flexibility for occasional users, semi-professionals and professionals for tasks such as hedge trimming, edging, pruning, cleaning and cultivating, and more attachments are being developed. This system not only saves on storage and transportation space, it allows for significant cost savings as well. Here is just a sampling of what is available...
the "other" multi-task unit.
If you want your power down low (gravity friendly) Stihl has the machine.
Stihl has given this whole process a lot of thought and has come up with a winner system for the ground. See the list of attachments here.