SkyVector.com should be a new entry of your web bookmarks ! In just one place, you have free and unlimited access to the world enroute maps (high and low altitudes). Zoom in and out, span around and check the perfect quality on your screen. Enter / edit a flight plan and it’s drawn in the next fraction of second.
You will also find weather stations reports (METAR, TAF, SIGMETS), NOTAMs, charts and sectional maps for USA.