You know, it really is amazing how God uses us in each others lives and how He can use certain people to impact others that you or I could never reach in the same way.
The really good thing is that most of the time, we really don't have a clue how God uses us. I think if we really saw the whole picture, many of us, myself included, would probably struggle a lot more with our pride.....although from time to time it is neat to see a tiny glimpse of what God is doing in and through us.
Really it is all about keeping our eyes on Jesus and obeying him, and the ways that our lives get used to His glory and shown as a testimony to the watching world around us are a part of what happens as we live for Him.
That impact whether great or small is significant and totally because of His grace to us.
Proverbs 27:17 "As iron sharpens iron, so one person sharpens another."