diff --git a/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitor.java b/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitor.java
index 31be7918f..6ecd354de 100644
--- a/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitor.java
+++ b/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitor.java
@@ -18,7 +18,7 @@ import net.i2p.util.Log;
  * Main driver for the app that harvests data about the performance of the network,
  * building summaries for each peer that change over time. <p />
  *
- * Usage: <code>NetMonitor [configFilename]</code> <p />
+ * Usage: <code>NetMonitor [configFilename] [--routers filename[,filename]*]</code> <p />
  *
  *
  *
@@ -41,15 +41,20 @@ public class NetMonitor {
     private int _exportDelay;
     private String _exportDir;
     private String _netDbDir;
+    private String _explicitRouters;
     private int _summaryDurationHours;
     private boolean _isRunning;
     private Map _peerSummaries;
     
     public NetMonitor() {
-        this(CONFIG_LOCATION_DEFAULT);
+        this(CONFIG_LOCATION_DEFAULT, null);
     }
     public NetMonitor(String configLocation) {
+        this(configLocation, null);
+    }
+    public NetMonitor(String configLocation, String explicitFilenames) {
         _configLocation = configLocation;
+        _explicitRouters = explicitFilenames;
         _peerSummaries = new HashMap(32);
         loadConfig();
     }
@@ -120,6 +125,8 @@ public class NetMonitor {
     public int getSummaryDurationHours() { return _summaryDurationHours; }
     /** where should we read the data from? */
     public String getNetDbDir() { return _netDbDir; }
+    /** if specified, contains a set of filenames we want to harvest routerInfo data from */
+    public String getExplicitRouters() { return _explicitRouters; }
     /** 
      * what peers are we keeping track of?  
      *
@@ -203,10 +210,30 @@ public class NetMonitor {
         }
     }
     
+    /**
+     * main driver for the netMonitor.  the usage is:
+     * <code>NetMonitor [configFilename] [--routers filename[,filename]*]</code> 
+     */
     public static final void main(String args[]) {
-        if (args.length == 1)
-            new NetMonitor(args[0]).startMonitor();
-        else
-            new NetMonitor(CONFIG_LOCATION_DEFAULT).startMonitor();
+        String cfgLocation = CONFIG_LOCATION_DEFAULT;
+        String explicitFilenames = null;
+        switch (args.length) {
+            case 0:
+                break;
+            case 1:
+                cfgLocation = args[0];
+                break;
+            case 2:
+                explicitFilenames = args[1];
+                break;
+            case 3:
+                cfgLocation = args[0];
+                explicitFilenames = args[2];
+                break;
+            default:
+                System.err.println("Usage: NetMonitor [configFilename] [--routers filename[,filename]*]");
+                return;
+        }
+        new NetMonitor(cfgLocation, explicitFilenames).startMonitor();
     }
-}
\ No newline at end of file
+}
diff --git a/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitorRunner.java b/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitorRunner.java
index 6b2b03e96..116ba7471 100644
--- a/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitorRunner.java
+++ b/apps/netmonitor/java/src/net/i2p/netmonitor/NetMonitorRunner.java
@@ -7,6 +7,7 @@ import java.io.FilenameFilter;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
+import java.util.StringTokenizer;
 
 import net.i2p.data.DataFormatException;
 import net.i2p.data.RouterInfo;
@@ -128,12 +129,35 @@ class NetMonitorRunner implements Runnable {
      * @return list of File objects pointing at the routers around
      */
     private File[] listRouters() { 
-        File dbDir = new File(_monitor.getNetDbDir());
-        File files[] = dbDir.listFiles(new FilenameFilter() {
-            public boolean accept(File f, String name) {
-                return name.startsWith("routerInfo-");
-            }
-        });
+        if (_monitor.getExplicitRouters() != null) {
+            return listRoutersExplicit();
+        } else {
+            File dbDir = new File(_monitor.getNetDbDir());
+            File files[] = dbDir.listFiles(new FilenameFilter() {
+                public boolean accept(File f, String name) {
+                    return name.startsWith("routerInfo-");
+                }
+            });
+            return files;
+        }
+    }
+
+    /**
+     * Get a list of router files that were explicitly specified by the netMonitor
+     *
+     */
+    private File[] listRoutersExplicit() {
+        StringTokenizer tok = new StringTokenizer(_monitor.getExplicitRouters().trim(), ",");
+        List rv = new ArrayList();
+        while (tok.hasMoreTokens()) {
+            String name = tok.nextToken();
+            File cur = new File(name);
+            if (cur.exists())
+                rv.add(cur);
+        }
+        File files[] = new File[rv.size()];
+        for (int i = 0; i < rv.size(); i++)
+            files[i] = (File)rv.get(i);
         return files;
     }
     
@@ -146,4 +170,4 @@ class NetMonitorRunner implements Runnable {
             Thread.sleep(_monitor.getHarvestDelay());
         } catch (InterruptedException ie) {}
     }
-}
\ No newline at end of file
+}