I would appreciate a column for date / time scanned as mentioned in an other post. And maybe an optional random scan of ip ranges. This would make scanning more flexible for changing ip addresses. And the feature i really wood appreciate is an PAUSE / CONTINUE button. And an other term is the performance. Always when network scanner is scanning an IP range my computer lacks on performance (Intel P4 2,8 GHz, 1GB RAM, ADSL 6000). A Rescan function for a single IP would be very nice too, so I don't have to ping manually an IP which was scanned a few hours ago to check if the IP is still alive.
To reduce the performance degradation, you may try to decrease the number of concurrent threads (see the Options). We also just added the 'Rescan' menu item as you requested. We'll consider your remaining wishes and may add them in the future.