Sometimes worth having a free Google Mail account (7 GB space allowed, and since user views items via web browser, it's up to them as to whether {or if} they wish to download any particular items). I have a friend in the USA who often sends clips off American web sites, sometimes a few MB at a time, and with them going into my GMail account I can view them without needing to download them onto my mobile phone).
YouSendIt (as mentioned above) is a good option if you have files of say 15 MB to 50 MB - some mail accounts don't allow items above 10 MB to be sent.
GMail has a maximum limit of 25 MB for incoming mail items.
If you ever try to send someone a binary (.exe or .com) then many mail services will block the sending (in case it is someone sending a virus).
You can make a .ZIP file and send that with the binary file inside.
I would suggest sending a note beforehand, saying that you are sending them a binary, and even include your phone number or similar (so the recipient knows it is you and not some virus sending the message) and to allow them to query the reason for sending a binary.
It's not especially relevant for this question of sending some photos, but there might be some other time when sending a binary is important (eg to help someone with same type of mobile phone, or camera, or whatever).