Question: I was wondering if anyone knows of a free WMS of imagery that I could use within QGIS. The imagery does not have to be high resolution (Blue Marble even). I would like to have a base imagery feed from a WMS.

Any help would be appreciated.

Thanks...

Answer: 
As Curlew stated in their answer, up the openlayers plugin. between bing mapping and google maps on this you basically have most areas with aerial photography.

i asked previous

[Digitizing from OpenLayers Plugin in QGIS, or create raster?](https://gis.stackexchange.com/questions/50130/digitizing-from-openlayers-plugin-in-qgis-or-create-raster)

See this for saving the images and removing the need to load the entire globe.
You may use the USGS WMS:

Here are the links for their aerial 1ft and 1m service (note, sometimes they are down):

[The National Map - Service Endpoints](http://viewer.nationalmap.gov/example/services/serviceList.html) 

**\* USGS 1 foot imagery -** <http://raster.nationalmap.gov/arcgis/services/Orthoimagery/USGS_EROS_Ortho_1Foot/ImageServer/WMSServer?request=GetCapabilities&service=WMS>

**\* USGS 1 meter imagery -** <http://raster.nationalmap.gov/arcgis/services/Orthoimagery/USGS_EROS_Ortho_NAIP/ImageServer/WMSServer?request=GetCapabilities&service=WMS>