I'm not sure if I can narrow down an exact top ten, but these are amongst my favorites:

Ayumi Hamasaki - "M (Above & Beyond Remix)"
Chicane - "Saltwater"
Chicane - "Autumn Tactics"
Delerium featuring Sarah McLachlan - "Silence (DJ Tiësto's In Search Of Sunrise Remix)"
Paul Oakenfold - "Southern Sun (DJ Tiësto Remix)"
DJ Tiësto - "In My Memory"
Oceanlab - "Sky Falls Down"
Oceanlab - "Clear Blue Water (Ferry Corsten Remix)"
Billy Ray Martin - "Honey (Chicane Club Mix)"
Sarah McLachlan - "Fear (Hybrid's Super Collider Remix)"